It goes without saying: the best way to increase the difficulty of AOW3 is to play against actual humans. But since some don't want to do that, there is value in finding ways to increase the difficulty of Versus AI games as well.

This is a guide for advanced players who want to further increase the difficulty (and fun!) of winning against 5+ Allied Emperor AI opponents by introducing restrictions and challenges (e.g., "you can only use T1 Orc Spearman", "you can only use Hero units"). This guide assumes you are playing the latest complete version of Age of Wonder III (v1.802) with all DLC installed (i.e., Golden Realms + Eternal Lords expansions).

This guide assumes you are familiar with basic AOW3 gameplay and strategy, as well as the Necromancer units, Empire Upgrades, Strategic Spells, and Combat Spells. You can read up on this information at Fandom's AOW3 website[age-of-wonders-3.fandom.com], if necessary. For introductory and advanced strategy video walkthroughs for AOW3 more generally, Bob at Black Arrow Gaming is good for foundational strategy, whereas Hiliadan and Marcus Persson are good for pro-level strategy. I've learned a lot from these folks since I started playing AOW3 in 2016. Other helpful resources include Hiliadan's AOW3 Wiki tutorial videos[age-of-wonders-3.fandom.com] webpage and AOW3 Strategy and Tactical Guide [age-of-wonders-3.fandom.com]webpage.

Below I will outline the various challenges that I have come up with over the last 5 years of playing AOW3. I have been able to complete them all successfully, though not necessarily on the first try. Each challenge is described, a written tips guide is provided to help you succeed at the challenges, and links to YouTube videos of my successful attempts are also provided in case it is of use or entertaining to you.

Please note that this guide refers to content in my first AOW3 guide entitled "Necromancer: Defeating 7 Allied Emperor AI's by Turn 50 (w/ Video)", so you may find it helpful to read that guide alongside this one.

This first section addresses the 40-Turn Head Start Challenge. When you sit in your base and do nothing for 40 turns, it requires some strategy adjustments to still pull out the win.

Here's a 40-Turn Head Start Challenge video walkthrough where I do nothing for the first 40 turns of the game to give my 5 allied Emperor-level AI opponents a head start, beating them in Turn 122. I also refuse to recruit any Heroes after the first, leaving me with 1 Leader and 1 Hero for the first half of the game until I start ghouling enemy Heroes. Normal Defender Strength with Shadowborn Adept and Destruction Adept/Master. For this campaign, I pre-selected each of my opponents to use leaders and class/race combinations that tend to be more difficult opponents for a Necromancer to face. This was a brutal challenge. The playlist is 90 videos long (85 episodes worth of content) and is a total of 84 hours of gametime. Instead of recaps at the end of each turn (or set of turns) like for many of my other strategy series' playlists, I decided to record everything to let you get a sense of how I made each individual decision on the map and in combat. It's not always the most exciting thing to watch, given that I take lots of time to think through my options during tough battles as there was often very little room for error given the nature of this challenge. It was super important for me not to lose important troops and heroes when possible. Also, here is a list of links to video episodes from the series featuring interesting/pivotal battles[docs.google.com] I fought during this challenge.

Here are my suggestions for this specific challenge:

• When you allow your AI opponents to get a 40 turn head start on you, there is tremendous pressure to make up for lost time by building up your army at breakneck speed. You need to get your Leader and Hero (both Necromancers) leveled up as fast as possible so you can use them to start ghouling T2/T3/T4's as soon as possible. You'll have enemy armies composed of T3s/T4s approaching your capital in the first 10-20 of your movement and city production (i.e., turn 50-60), so you need to be ready.
  
• Unless you have a starting position where the terrain and map position allows you to easily defend your capital and many cities near it, you will have to be ready to survive with just a few immediately-adjacent cities under your control the majority of the game, defended by 1-2 stacks of good units. This means that you won't be making a lot of gold/mana/research per turn from cities, which means that you'll need to count on Hasty Plundering enemy cities every few turns in order to earn enough gold/mana to keep your gold/mana at sufficient levels. When I did this challenge, for most of the game I was running on deficit spending, such that I was losing 200-300 gold a turn due to high upkeep costs that I was not able to cover by city income alone. But I found it essential to be willing to spend the army upkeep costs in order to have a big enough military to both defend my small core territory and also send out 2 strike forces of 2-3 stacks each into the remainder of the map. I thought about abandoning my small territory entirely and just relying on Hasty Plundering to cover my upkeep costs, but ultimately decided that would not be a more efficient choice. I recommend picking a few immediately-adjacent cities that you can connect with roads, which allows you defensive stacks to defend/retake any city in the small cluster in a timely manner. It was common for several of my cities in my small territory to be threatened at the same time, which required tough choices about what to defend vs retake.
  
• I recommend identifying the city in your small territory with the best production potential and making that your item forge city, which you'll want to get up and running as early as possible. Because item upkeep costs are so brutal, I recommend forging many Helmets with "Bringer of Goodwill" property which will cut the upkeep costs of that Hero's army in half, which is essential when your armies have a lot of expensive T3s/T4s.
  
• If you are facing a dreadnought AI, it requires some special considerations that other classes don't require. For one, the risk of instant death from bombard/cannonball is real, so you need to be ready to use Greater Reanimate Undead to bring those fallen Heroes/valuable units back before closing out of the battle. The Undying Army spell is also handy (though there is a risk it can be disjuncted) for giving your units a second chance at life. Definitely prioritize the Undying individual hero upgrade on all your Necromancer Heroes. Items/mounts that grant physical or fire immunity are valuable, as are Dreadnought Heroes' Guardian Flame buff ability. Full fire immunity for Heroes is useful especially when dealing with Juggernauts but especially Flametanks. Also, your Item Forge priorities change such that the following items become particularly useful: melee weapons with Demolisher & +2 Shock Damage & +2 Cold Damage, ranged weapons that deal pure shock, for ranged heroes a quiver that adds +2 Shock Damage & +2 Cold Damage to ranged attacks and a helmet with Seeker, Stunning Touch use items, and if you have the capacity a series of items with +20% fire resistance.
  
• You need to scout efficiently to allow yourself to quickly find the Leader + Capital of the scariest AI opponents (like Dreadnoughts) so that you can take them out promptly. It is not necessary to plunder every city in your path; if you know where a Leader and Capital are then don't waste time trying to take all their other cities. The Explorer specialization's Master Cartographer empire upgrade is helpful for this if you can spare a specialization slot.
  
• If you have a tough battle ahead of you, send a small portion of your troops into battle against the stack in question and give the AI a chance to cast spells (hopefully not damage spells) that reduce their casting point pool, but retreat before you start taking damage (kite them until then). Then, send in one additional fresh unit to initiate battle and repeat the process above. Keep doing this until you've drained all their casting points, then send in the rest of your troops and go in for the real battle--this lets you cast key spells without risk of disjunction. The cost is that your troops that did prior retreats will have 0 strategic map movement. I had to do this a few times to help me avoid major losses in a few battles. Of course this cheese tactic is only available on offense, not defense during turn-over.
  
• Make sure of builders to place forts on key resource structures to boost your resources, as you will have few cities producing resources for you. They can also build roads ahead of key stacks and watchtowers to give you vision.
  
• Because you'll be facing much tougher AI stacks, it is particularly valuable to do smart item forging and hero upgrading to help create melee heroes that can infinitely tank melee damage (from non-machine/undead foes) via Life Steal-imbued weapon and Tireless-imbued boots. Defender-imbued shield, +10hp-imbued Torso chestpiece, Strong Will-imbued helmet, and First Strike-imbued accessory help too. Versus machines and undead, a high HP-theocrat can tremendously increase survivability of a melee tank Hero via Absorb Pain ability. As always, check out the Item Forge Priorities tab of my AOW3 Google Spreadsheet[docs.google.com] for advice.
  
• It is normal to fail this challenge the first few times, so go in expecting to have to retry a few times before getting on a viable run.

When you only allow yourself to use Hero units in battle and never use other military units, it's a fundamental change.

Here's a video walkthrough playlist of how I beat this challenge.

Here are my suggestions for this specific challenge:

• There are two overarching approaches to this challenge. The first is to build up at least 12 heroes (through recruitment, but mostly ghouling) and then split them into two different stacks, one which will guard the 3-6 cities in your starting zone (ideally a corner) of the map. This allows you to hold onto cities throughout the game (or at least as long as that home-guarding stack remains strong enough to repel invaders), which has the advantage of ensuring adequate mana supply to fuel all your battle spellcasting and your multiple item forges that you should have producing items for your heroes, as well as enhanced knowledge accrual to help you climb the tech tree. The second approach is to Ghoul the first few cities you conquer (but leave them defenseless to get as much resource from them as possible before they are inevitably captured by independents or opponents) and then Hasty Plunder the remainder. I took the second approach in my Heroes-Only Challenge video series and it worked well. I was able to hold on to a city in the upper left hand corner for a fairly long time undetected by opponents, which let me rush forge many items for my heroes.
  
• Item forging is essential since your heroes are doing all the work. For suggested equipment arrays for your various heroes, see the "Item Forge Priorities" tab of my AOW3 Google Spreadsheet[docs.google.com]. You must equip them as strongly as possible as early as possible to help you avoid unnecessarily losing heroes during tough battles. One goal is maximizing survivability, another goal is facilitating successful AI hero ghouling, and a third goal is maximizing damage output. The "Item Forge Priorities" tab also covers ideal races and classes for key hero roles. Ideally, you'll want some melee tanks (some who can deal with machines if versus dreadnoughts or undead if versus necromancers, but most who can deal with flesh/incorporeal), some ranged damage dealers/stunners/casters, and a few theocrat Absorb Pain sponges who will help protect your valuable heroes.
  
• The "Heroes-Only Challenge" tab of the aforementioned spreadsheet goes into detail about what the ideal stack leader leveling looks like for different hero classes (Warlord is ideal stack leader), priority combat spells, and abilities/spells that increase changes of successfully ghouling enemy heroes.
  
• Ghouling enemy heroes is of utmost importance. When I did this challenge, I was only able to recruit a few heroes before I lost control of all cities; you can still recruit heroes that will offer to join next to cities you just conquered and are in the process of plundering, thankfully. By the time I finished the challenge, I had ghouled about 25 enemy heroes. Because your success rests on building up your number of ghouled heroes as fast as possible, you'll want to be thinking about the implications for things such as specializations, hero upgrades, item forging, and troop movement. First, I highly recommend the Wild Magic Adept specialization and getting to the Degenerate battlefield spell as quickly as possible, as this drops resistances to all damage channels including spirit, which is very helpful when trying to land a successful ghouling blow. It even makes it possible to ghoul enemy heroes with the strong will 100% spirit protection upgrade, which will drop resistance to 60% and make it possible to inflict despair and other debuffs enough to give you a fair shot at ghouling. You'll still want Destruction Adept for Hasty Plunder, as that's essential to the strategy. You have flexibility with the third specialization (e.g., water adept vs. dreadnoughts or other undead, etc.). However, having done a few more small-army challenges since I did this challenge, I believe the third specialization should be Explorer, as Master Cartographer is essential for efficiency. Second, regarding hero upgrades, there are certain skills that will be helpful for the ghouling process (see the spreadsheet for details). Third, useful items to forge or acquire include Weakening and Dominate. Fourth, when it comes to troop movement, you will want to (a) maximize getting experience on your heroes as quickly as possible, (b) encounter enemy AI not too early but not too late--you want to be ready to defeat early armies the AI is sending out but don't want them to get too powerful before encountering them for the first time--so that you are ready to engage their initial armies, not lose your own heroes in the engagements, and ensure a high probability of ghouling every enemy AI hero you cross paths with. You need to succeed with your ghouilng as much as possible at it will make the difference between a win and a loss.
  
• You'll want to research Harbingers of Death empire upgrade as soon as possible as it ensures all heroes can be healed by the Heal Undead ability (and the Heal Undead items you should be Item Forging and getting distributed to all your heroes) and, more importantly, can be brought back with Greater Reanimate Undead, as some will inevitably get killed during tough battles and it's nice to be able to bring them back in a pinch.
  
• Regarding valuable combat spells to research and cast, death ray will help with early battles, stiffen limbs will be used frequently in early battles and is absolutely essential to early survival, desecration/dark gift/syphon life is situationally useful in certain battles, scourge of undead and undying army can be incredibly helpful especially if you can avoid disjunction by AI.
  
• Regarding valuable strategic spells to research, cast, and regularly reinforce against disjunction: Hasty plunder is essential. Scorched earth is situationally helpful for early conquered cities that you want to hold for a time but don't want to let fall into enemy heads. Whispers of the Fallen is essential for research progression. Enemy of the faith is useful for doing heavy damage to enemy support units. Power Ritual is useful for increasing melee damage dealt. Damnation is useful when preparing to siege a heavily defended city.
  
• Regarding valuable empire upgrades to obtain, shrines of unlife helps early on with mana production from city shrines, master of puppets increases happiness of your ghouled heroes, harbingers of death (for reasons mentioned above), necromancy (to boost spell casting by Leader).
  
• Because you have so few army stacks and it is safest to keep them all together (at least until the late game when most AI have been killed), you won't be able to conquer/hold multiple areas of the map. I recommend Hasty Plundering as you go. You will want to prioritizing identifying who the most troublesome AI opponents are (in order from approximate deadliest to easiest to deal with: Dreadnoughts, Theocrats, Sorcerers, Rogues, Warlord, Necromancer, Arch Druid) and prioritize killing them first. This requires identifying where their Leader is and their capital and trying to eliminate both in close succession to prevent respawning/throne relocation. In the early and mid parts of the game, even if you plunder all cities in your path, the multiple AI will just build settlers and re-settle those razed cities, so at least in my case I had to go through the entire overworld map a second time with eliminate cities that had been rebuilt. This is why focusing on taking AI out of the game by killing leader+capital is your number one priority. Moving about the map in a way that allows you to fight and ghoul enemy non-leader heroes is also important for your overall success.

The "Single Stack Challenge" requires you to own/use a maximum of 6 military units at any given time, for the entire duration of the game. Any time you acquire an additional military unit (clearing site reward, tribute, conversion, summoning, building, etc.), at the next possible opportunity you must immediately disband military units to ensure you have a maximum of 6 military units. Non-military units (builders) do not count against this military unit limit.

Here's my Single Stack Challenge video walkthrough playlist, where you can see how I completed this challenge.

Here is my advice on how to beat this challenge:

• My personal strategy for beating this challenge was to keep my starting army alive and slowly replace non-hero units with hero units until I hit 5 hero units in a single stack, reserving the 6th spot for serially summoning cherubs to facilitate scouting in order to more quickly find enemy AI leaders and capitals.
  
• I used Human Theocrat because (a) Divine Justicars is the most efficient way to avoid losing units, (b) humans can start with cavalry that have the capacity to evolve into knights at gold rank, and (c) humans can start with priests that have the capacity to Bestow Iron Heart, Heal (once Order of Healing empire upgrade is researched), and Inflict Dazed at gold rank. High Elf (stunning and healing storm sisters) and Draconian (hatchlings evolving into potential T2/T3; regrowth potential on Crushers/Chargers with requisite Race Governance update) are additional race options.
  
• My recommended build order for the Human Theocrat Leader is described in the first table within the "Single-Stack Challenge" tab of my AOW3 Google Spreadsheet[docs.google.com].
  
• Unlike the Heroes-Only Challenge described above, you will have fewer hero units to work with, so you need to be careful about what heroes you allow to earn a spot in your lineup. You'll need at least 1 melee tank hero ready to switch up equipment to take on flesh/incorporeal (life drain + tireless gimmick) or machine or undead, at least 1 seeker-helmet-wearing ranged hero, and preferably 2+ heroes that can do ultimate battlefield summons (e.g., chaos rift, beast horde, scourge of undead). Go for hero class variety rather than redundancy, generally. See the "Item Forge Priorities" tab of my AOW3 Google Spreadsheet[docs.google.com] for guidance on how to achieve a good set of heroes.
  
• I recommend that you build your Theocrat Leader to be a high-HP ranged damage dealer that stays out of trouble to ensure Divine Justicars stays active to resurge any units that die. It is not uncommon for the AI to take out your capital, which means losing your Leader is an automatic game over. It is much better to keep your Leader alive even if it means your other units take more damage.
  
• You don't have to replace all your troops with hero units over time, as there are a few T3/T4 units that could be just as valuable as a hero unit to retain in your stack. Having at least 1 non-hero unit is especially useful because you can concentrate experience gain on them once your heroes have hit their level caps, as heroes can't keep increasing HP but non-hero units can via additional Champion levels. Recommended T3/T4 units to consider including in your single stack are described in the "Single-Stack Challenge" tab of my AOW3 Google Spreadsheet[docs.google.com].
  
• Priority combat spells for your heroes to pick up are described in the second table within the "Heroes-Only Challenge" tab of my AOW3 Google Spreadsheet[docs.google.com].
  
• In terms of specializations, I recommend Destruction Adept (Hasty Plunder and Scorched Earth to allow your invading stack to never stop moving after taking a city and keep your mana pool high), Explorer (Master Cartographer facilitates efficient pathing toward enemy capitals), and Water Adept (anti-machine and anti-undead Rot spell is handy). Water Adept can be swapped out with another specialization if you believe you won't need Rot.
  
• Plan to Hasty Plunder cities that won't be able to defend themselves as released vassals (this includes most cities you capture from the AI).
  
• I recommend clearing out your corner of the map before plunging into AI territory, as you want to be sufficiently leveled before facing 2/3 AI stacks at a time. It also allows you to obtain some vassals to increase your resource income (mana and research are the most valuable; you'll have plenty of gold come mid game and beyond as military upkeep is minimal as is infrastructure spending). Hostile independent cities and dwellings at war within you upon meeting them should be conquered and released to vassal. Friendly independent cities/dwellings should be peace treaty'd and made vassals as soon as possible. Ideally, you can clear key sites in the cities' radii to help increase the income they will send your way as vassal. We don't want to Absorb independent cities and Dwellings because, given the nature of the challenge, you won't be able to spare troops to defend them. It is better to keep them as vassals so that they can defend against roaming neutral mobs in early and mid game (they will eventually be easily killed by enemy AI in mid to late game).
  
• In your capital, get your builders hall up first, build a few builders (a few tasked with meeting independent cities and dwellings early before roaming mobs make this impossible, one or two following your military stack to build resource-gathering fortresses, one building watchtowers to give advance notice of AI advance on capital) in early game, get a shrine up for mana production, then get the Siege Workshop and Masters Guide structures online to boost production capacity before building the Item Forge and starting to forge items for your heroes for most of the rest of the mid and late game.
  
• To help ensure your capital stays in your hands into late game, once you've done one loop through your corner of the map with your starting stack, consider leaving one of your 6 units behind in your capital to defend it (see my Human Priest defending my capital like a champ in this video from my challenge series). Ideally this unit has a ranged ability and a few champion experience levels. I found the tradeoff of having one fewer unit in my main stack to be worth the benefit of being able to hold my capital for a much longer period of time (which means I could forge a lot more items for all my heroes). Of course, if you can clear out the 16 hexes around your capital in every direction from roaming neutral mobs you may not even need to defend the capital from neutral mobs in early and mid game, but it will fall quickly to the first AI scout that comes upon it.

The "Weak Starting Army Only Challenge" requires you to toggle the "Starting Units" setting to "Weak" and then only use your 6 starting military units (Leader, first Hero offering to join on T1, one T2, three T1's) for the entire duration of the game. If you lose one of your 6 starting units, you may not replace it. You may not build or summon additional military units. Any time you inadvertently acquire an additional military unit (site reward, conversion, etc.) you must immediately disband that unit. Non-military units (builders) do not count against this military unit limit and may be built and used as normal (though I like to play with Settlers/City Founding toggled off to increase difficulty).

Here's my Weak Starting Army Only Challenge video walkthrough playlist, where you can see how I completed this challenge.

Here is my advice on how to beat this challenge:

• As with the Single Stack Challenge described above, I used Theocrat class because leveling my Leader up to Level 11 so they can take the Divine Justicars upgrade helps greatly decreases my chances of losing one of my starting military units, which would greatly hurt my chances of beating the challenge.
  
• I recommend using the High Elf race, because you have a chance to for your 3 starting T1 units to be High Elf Initiates (an irregular T1 unit). Initiates evolve at gold rank into Storm Sisters, which have total awareness, significant shock protection, can use Heal ability (with Theocrat's Order of Healing empire upgrade) and Inflict Stun at gold rank. Draconian is an additional viable race option, as their (1) hatchlings evolve at gold rank into potential T2/T3 units and (2) Crushers/Chargers gain the Regrowth ability (with requisite Race Governance upgrade) that when paired with several Champion levels can result in high HP units that benefit greatly from the regrowth.
  
• My recommended build order for the High Elf Theocrat Leader is described in the "Weak Starting Army Challenge" tab of my AOW3 Google Spreadsheet[docs.google.com].
  
• Once your two heroes are max level, you can focus experience on your non-hero units into perpetuity, which benefit from the increased HP that comes with additional Champion experience levels. When I beat this challenge, I ended up with a Champion 13 unit with 200+ HP, which felt awesome. High HP non-hero units help give you a fighting chance when facing off against multiple high power AI stacks in late game.
  
• Ideally, the hero who offers to join you on Turn 1 (who will be the only other hero in your army) is a race/class that does well in the melee hero role. You need a good melee tank that can use the life drain/tireless mechanic to grind through lots of enemy AI units when facing 2/3 full stacks. See the "Item Forge Priorities" tab of my AOW3 Google Spreadsheet[docs.google.com] for details on how to build and forge items for such a tank.
  
• My advice in the Single Stack Challenge section (see above) regarding keeping your Theocrat leader alive, specializations, item forging for the heroes, troop movement, capital build order, and plundering vs. vassaling applies to this Weak Starting Army Only Challenge as well. It is less important to hold your capital into the late game for this challenge because you only have 2 heroes to outfit with items via your capital's forge, which can be done by late midgame usually.

The "Tier 1 Orc Spearman Only" Challenge requires you to field tier 1 irregular unit Orc Spearman in battle for the entire duration of the game. Thus, any time you acquire additional military units (clearing site reward, tribute, conversion, summoning, building, etc.), at the next possible opportunity you must immediately disband them. The Orc Warlord Leader must never get involved in a battle, or the challenge is automatically failed (you will want to hide the Leader in the corner of the map to prevent the Leader from being physically present during a battle). The Leader is allowed to cast strategic spells and combat spells from afar but may never use a combat spell that summons units. Non-military units (builders) do not violate this restriction and may be built and used as normal (though I like to play with Settlers/City Founding toggled off to increase difficulty).

Here's my T1 Orc Spearman Only Challenge video walkthrough playlist, where you can see how I completed this challenge.

Here is my advice on how to beat this challenge:

• See "T1 Orc Spearman" tab of my AOW3 Google Spreadsheet[docs.google.com] for advice on what researchable upgrades (empire upgrades, combat spells, strategic spells) are high priority for beating this challenge. The Explorer specialization empire upgrades are the highest priority, having a few useful battlefield spells early will help with tough site clearing, raise militia is essential for early spearman generation, global assault is the number one late game priority, and most of the empire upgrades are great for improving your macro/economy. Having completed the challenge, I don't think that Destruction Adept and Shadowborn Adept were worth taking up specialization slots for, so I provide some additional recommended specialization options lower in the table. Greygaurd specialization skills could be amazing but you will likely become and stay evil aligned due to all of the migrating captured cities to Orc race that you'll want to be doing, so this was not one of the specializations I recommended as an alternative.
  
• For some context around this challenge: I knew I wanted to try a Tier 1 irregular unit challenge but wasn't sure which race/class combination would be good. After researching my options, I determined that Orc Spearman would be one of the best T1 irregulars to use, so I might as well make the challenge specific to Orc Spearman, rather than allowing the player to use a mix of different races, which could make things easier on the player. Orc Spearman are great because they have shield for additional defense, sprint for mobility and flanking, war cry for enhanced melee damage, victory rush to regain some HP after each victory, and armor piercing at gold rank. Warlord is a great class because their upgrades often benefit the T1 Orc Spearman, such as Bloodbath and other great melee-centric combat spells and Raise Militia for early spearman generation and Global Assault for amazing late game bonuses to the strength of the spearman. I strongly considered Rogue as an alternative class due to some irregular bonuses but Warlord proved to be the best pick.
  
• Unlike all my other Challenge series to date, this was very macro/economy focused rather than purely combat strategy focused, as there are significant limits on what you can do when you can only use Orc Spearman in combat. Thus, I knew that I would have to win by overwhelming my 5 Emperor-level AI opponents with hordes of spearman. To accomplish this, you have to acquire and hold a great number of cities. Unlike past challenges, plundering cities and moving on with your forces is not as helpful because you really do need to maximize unit production via those newly conquered cities. So, I knew I would have to be able to defend cities that I had taken. I decided to send large numbers of troops in a manner that ensured that my front lines were populated by a strong force and no enemy opponents were left standing behind my front lines. Thus, I was careful about clearing out independent creep spawners and searching all areas for AI troops that might be sneaking around, as I was not going to be able to retain a large number of spearman behind my lines. By making sure there was no danger behind my front lines, I could absorb/migrate those cities to Orc and leave them virtually undefended. I only vassalized dwellings and those cities not yet in my front lines. I did encounter one global event (Rise of the Fire Rogue) that forced me to deal with randomly spawning enemy units far behind my lines, but the fact that I was producing Spearman in most cities throughout my entire capital means I was able to pull together small groups of Spearman quickly in key spots in my empire to deal with these random spawns without much trouble.
  
• In early game, most acquired cities starting to immediately produce Spearman. However, I would first build a Builder's Hall if the city's production was not high enough to allow for production of Spearman in one turn. Likewise, when low on mana (I am constantly spamming Raise Militia and combat spells), I would build shrines. If I could build a Mercenary Camp (when Trading Post is in city radius), I did that first, as it gives +1 def and +1 melee/ranged attack to irregular units, so my Spearman could benefit from this upgrade. I occasionally built laboratory+observatory in certain cities in order to get key structures into the city radius faster and boost my early game research.
  
• Throughout the game, I built plenty of Builders to construct roads/bridges to help newly built Spearman move quickly to the front lines, help increase my resource intake (fortresses), and keep an eye on key fronts (watchtowers).
  
• In late game, I used certain cities (that were well developed by the enemy AI before being captured by me) to build to Grand Palaces to increase my casting points. If you are a perfectionist, you can set up city waypoints so that every time a Spearman is built in a city it will head to the waypoint you set for the city (a spot near the front lines, for example) without delay. However, you can reduce the number of clicks you need to make if you allow a given city to produce 6 Spearman before sending them off as a single stack to a spot on the front lines.
  
• If you are concerned about out your Leader getting attacked (thereby failing the challenge), build an Item Forge and create an item that will give you terrain concealment of some kind and hide your Leader in a corner of the map on the terrain type that will grant concealed status. And be sure to clear all spawn camps in a 16 tile radius of the Leader.
  
• Sieges are tough because Spearman can only bust down the 3 gate doors; they can't climb or bash walls. So you either need to defeat the enemy with lots of low damage ranged spear attacks, trick the enemy into charging beyond their walls, or use a split strategy in battle such that you keep their forces busy on one end of the wall while you sneak a Spearman up the other end to bust down the down after about 5 strikes, at which point you can stream Spearman into that hole. It is much more effective to do your fighting behind the enemy walls. With some sieges, you just need to be prepared to take heavy losses, which you can replace once you have many cities under your control popping out Spearmen each turn.
  
• Dreadnought Machines (flame Tanks and Juggernauts in particular) are tough to deal with, as are Theocrat Shrines of Smiting. I lost a lot of Spearman to Shrines during my match as it is very hard to balance avoiding grouping your units with getting enough up in their face to kill them quickly. Their ranged abilities melt Spearman.

The "Two Unit" Challenge requires you to limit yourself to only using 2 military units for the entire duration of the game (you can swap one out for a different one at any point, but for me I recommend that your two units be your leader (required) and the first hero that offers to join) Thus, any time you acquire additional military units (clearing site reward, tribute, conversion, etc.), at the next possible opportunity you must immediately disband them. Non-military units (builders) do not violate this restriction and may be built and used as normal (though I like to play with Settlers/City Founding toggled off to increase difficulty).

Here's my Two Unit Challenge video walkthrough playlist, where you can see how I completed this challenge.

Here is my advice on how to beat this challenge:

• See the "Two Unit" tab of my AOW3 Google Spreadsheet[docs.google.com] for advice on what researchable upgrades (empire upgrades, combat spells, strategic spells) are high priority for beating this challenge. The Explorer specialization empire upgrades are the highest priority so that you can research Master Cartographer, which will reveal the entire map, allowing you to efficiently plan your movement route (which is essential given that you only have 2 units, which must stay together for survival) so that you can guess where AI leaders are so that you can take each out before then taking their capital, eliminating them from the game. Earth Adept specialization provides Stoning for strong damage potential during early fights and Stone Skin for extra tankiness during tough fights. When I completed this challenge, I had opted for Earth Master for Slow and Earthquake, but in hindsight I recommend Destruction Adept instead so that you have access to Hasty Plunder (so that you can take a city and keep moving). If I had gone into late game in this challenge, perhaps Earthquake would have proved essential (massive damage to all units, with the exception of your two heroes, assuming you can get them floating boots or flying mounts, which is highly likely).
  
• I recommend Dwarf race for the +1 Defense and +1 Resistance, which help with survivability. I considered Orc but the -1 Resistance was risky, and also Draconian for the +10 casting points at Champion Race Governance level.
  
• I recommend Warlord class because (a) their combat spells are powerful and increase survivability of the extremely small number of units you are able to field in battle with this challenge (e.g., Last Stand, Phoenix Warrior, Steadfast Ward, Lion's Courage, Bloodbath) and (b) their empire upgrades include Thoroughbred Mounts (boosts HP of both of your mounted heroes by a whopping +15) and (c) they have a few useful strategic spells (e.g., Dread Siege to make tough sieges easier, The Draft for morale boost to get those crits).
  
• Advanced Logistics is worth going for mid-game to increase speed on the strategic map roads.
  
• As far as city management, I recommend clearing in the early game a 16 hex radius around your capital of all creep-spawning camps so that you can leave your capital safely undefended. Get a some production buildings up (e.g., Builder's Hall, maybe Siege Workshop), get a Shrine to increase mana, then build Lab/Observ/ItemForge and start rush-producing artifacts every turn. When I beat this challenge, I had started forging items by Turn 12. See the See the "Two Unit" tab of my AOW3 Google Spreadsheet[docs.google.com] for advice on what items are essential to forge and send to your two heroes to help them take on tough battles. The most essential items are a Life Drain weapon paired with Tireless boots, so that you can destroy endless waves of units (though machines, incorporeal, and undead will pose a challenge, which I address in the spreadsheet). Getting essential forged items to your heroes is the difference between life and death for this challenge.
  
• Throughout the game, I built plenty of Builders help increase my resource intake (fortresses) and keep an eye out for invasions and AI leaders (watchtowers). The extra mana helped make it possible to spend 250-350 mana a turn on a series of rush-produced items from my item forge, and the extra research helped me obtain key techs to build my survivability and map vision. Gold is not a limited factor, as you only spend it for rush-producing items and not much else.
  
• It's fine to vassalize cities you come across (whether by capturing and then releasing, or buying peace and then vassal status) on your side of the map to help boost mana and research accrual, but I recommend Hasty Plundering all cities on your enemy's side of the map to ensure you get some resources and deny them the ability to retake the cities. You won't be able to keep more than your capital defended, as your two-unit army will be far away from your empire in search of the enemy, so that's why you won't be doing much Absorbing.
  
• Dreadnought Machines, Theocrat Shrines of Smiting, and Necromancer Undead/Ghoul units are tough to deal with, so be careful when engaging these units in battle, and come prepared with the right combat spells and weapon. See my spreadsheet for more on this.

I welcome your constructive criticism and suggestions in the comments, and may update this guide in response to your feedback.

Please consider rating and favoriting this guide if you think it might be useful to other players looking to enhance their AOW3 experience.

Please check out my other AOW3 Guides:

• Necromancer: Defeating 7 Allied Emperor AI's by Turn 50 (w/ Video) - This guide is designed to help you defeat 4 to 7 allied Emperor-level AI opponents using the Necromancer Class. In-depth strategy advice for early, mid, and late game military and economic tactics.
  
• Wasteland Expansion & Nomad Campaign (AOW3 Mod by Gladen) w/ Video - In this guide I introduce readers to the Wasteland Campaign, which is a built-in campaign integrated into Gladen's AOW3 Mod called "Wasteland Expansion", which can be found in the AOW3 Steam Workshop. I also provide links to video overviews/playthroughs of the Reynald campaign and the Tanner campaign.

(Note: The contents of this guide, up until Fall of 2022, used to reside in my Draconian Necromancer guide mentioned above. However, I determined that these challenges really deserved their own separate guide, so created this as a separate guide in Fall of 2022.)