Elemental Affinity works for all five major Spell Skills, but you must be standing on the surface of the same type.

• Pyro => Standing in Fire
  
• Witchcraft => Standing in Blood
  
• Hydro => Standing in Water
  
• Aero=> Standing in Electrocuted Water
  
• Geo=> Standing in Poison or Oil

Fire and Witchcraft are the obvious choices for building a character around Elemental Affinity. Air would be virtually impossible to handle until you had over 100% resists, due to being stunned by standing in it. Water would work (and the player has access to Rain Skill very early), but the damage potential for the Battlemage is far greater with Fire. As for Geo - the player will end up being poisoned a lot (and there are many poison and oil surfaces in Divinity: Original Sin), however, a simple flame turns all poison and oil substances to fire and smoke.

Short Story: Eventually the battlefield almost always turns into giant pools of fire and blood, whether by the player's choice or enemy actions. So we might as well build a character class around this fact.

All that said: standing on a hazardous surface is problematic for the first few levels of the game as you will take some damage from the elements. (but don't let that deter you; you're going to be standing in fire one way or another, as the enemy will ensure that you do, especially in Tactician Mode). However, there are buffs you can (and should) use for the first half of the game, and then by level 12-15 you can acquire enough resist gear to prevent you from taking damage from your favored element (in our case, Fire). In addition, if you have the Demon Talent, you can raise your Fire resistance above the maximum of 100%, to 110%, where you will then heal from walking around in the element once your resist go over 100. And let me tell you: healing from fire is awesome.

The drawback to standing in fire in the early game is not nearly as bad as one thinks when you compare it to the power of firing off a lot of Pyro & Witchcraft spells for -1 AP. Not to mention that many, many battlefields will turn to blood and fire anyway, so we might as well make the most of it! This build gets stronger as the game goes along.

As I continue playing throught Divinity: Original Sin Enhanced Edition, I find certain Skills or Talents to be more or less useful. So I come back periodically and update this guide to be the most effective it can be.

I have updated this guide with a couple key changes.

Pyro Masters
I no longer recommend putting 5 Ability points into Pyro, and now advocate you only put 4 points in. It's simply not necessary. The only Master worth taking is Meteor Shower (and it is definitely worth taking). However, Infectious Flame and Immolation are not worth the 5-point investment. Neither do good damage. You're better off putting the points into your 2-hander for additional critical chance and damage. Because when your 2-hander crits, it does way more damage than either of those junky Master Skills will do.

Witchcraft Masters
I no longer recommend taking Resurrection as one of your two Witchcraft Master Skills. There are two issues that have come up through play:

1. Resurrection, as a Skill, has an 8-turn cooldown. You can reduce this with high INT, but it's still a cooldown. Scrolls have no cooldown; you can rez someone every turn if you have enough scrolls.
   
2. Late in the game, by the time you finally can get this Master Skill, you have more than enough cash to buy plenty of scrolls and stay very well stocked. The only drawback is having to teleport around to vendors to buy up their scrolls. But in my opinion, this is worth it, as you can spend this Master on another skill.

Shackles of Pain
I had previously recommended only putting 4 points into Man-At-Arms so you could acquire Flurry. That was before I tried out Shackles of Pain. You should definitely invest the full 15-points into Man-At-Arms and get both. Shackles of Pain is an absolutely devastating ability (when it lands, which is most of the time). The enemy you are tethered to will take all of the damage you receive. This means you want to get hit. When you couple this Skill with the Talent Morning Person (which allows you to be Resurrected with full health), you become the best way to kill boss mobs. Shackle them. Beat on them. Let them beat on you. Die. Get resurrected. Do it again. When you are Resurrected, all your cooldown timers reset. You can Shackle the enemy on your first turn back. It is a devastating way to deal damage on top of all the other tools you already possess.

You will have 18 Attribute points to spend on this build. Lone Wolf does not affect how many Attribute points you get to spend, so nothing changes between Regular and Lone Wolf.

• 15 Attribute points from leveling up.
  
• 1 Attribute point from the book that the Seller of Secrets offers
  
• 1 Attribute point from the Talent Bigger & Better
  
• 1 Attribute point [INT] from the Talent Know-it-All

Your final Attributes (without gear) will look like this:

STR: 11
DEX: 5
INT: 11
CON: 7
SPD: 9
PER: 5

You should primarily put points into STR and INT as needed (especially in the beginning). You will pump these numbers up beyond 15 very easily with the gear you get toward the end of the game. But you want CON=7 and SPD=9 in order to give yourself maximum Action Points per turn.

Your maximum Action Points per turn will be [Constitution] + 7, so 7 + 7 = 14.

Your turn Action Points will be 3.5 + ([Speed] * 0.5), so 3.5 + (9 + 0.5) = 8. This gives you two full swings with your 2-hander if you do not move (which you often will not) and you are not hasted.

A note on weapon choice: It may seem enticing to opt for dual-wielding weapons given that you get an extra weapon with stats/effects. However, unless you're a Rogue using DEX and Daggers, it's not worth it because of the superior range of the 2-handed weapons. 1-handed swords, axes and clubs will almost always require you to spend 1AP moving closer to your target before you can swing your weapons, leaving you with ONE melee action per turn. Your standard weapon swing with a 2-hander, and Crippling Blow, will cost 4AP, allowing you to pull off both in a single turn even when you don't have any AP saved from a previous turn. With 14 max AP per turn you can also pull off Flurry and Whirlwind. 2-handers win this.

A level-20 Regular character at the end of the game will have earned 54 Ability points to spend.
49 points from leveling
+2 points from the Talent All Skilled Up
+3 points from the Ability book sold by the Seller of Secrets

Ability Score => Total Points To Raise
1 => 1
2 => 3
3 => 6
4 => 10
5 => 15

As you can see, it gets costly to raise an ability beyond 3rd level. In addition, it pays to understand what each level grants you, in terms of known Skills.

Level 1 => 3 Novice Skills
Level 2 => 5 Novice Skills, 2 Adept Skills
Level 3 => 6 Novice Skills, 3 Adept Skills
Level 4 => 6 Novice Skills, 4 Adept Skills, 1 Master Skills
Level 5 => 6 Novice Skills, 4 Adept Skills, 2 Master Skills

So the only reason to even try and get a level 4 Ability is if there's a Master Skill worth taking. You cannot master everything. But, there are some masters worth taking, and we'll discuss those below.

2-Handed: 2 (3 points spent)
The extra points in this help with Critical Chance and damage multiplier. It's your primary weapon and you're going to use it a lot.

Armor: 3 (6 points)
Dropped and sold armor have superior resists and immunities to the armor you can craft. You want to look for armor with Fire Resist on it. In addition, these armors can still be augumented with additional resists with a ruby. However, the difference between dropped and crafted armor is that dropped armor will require 1 to 3 points in Armor Specialist. The armor will specify this on it and if you do not have the points you cannot wear it.

Man-At-Arms: 5 (15 points)
There are two Master Skills in this tree that are definitely worth it: Flurry and Shackles of Pain. Flurry is one of the single-most rewarding melee attacks to pull off. When buffed properly with Oath of Desecration, Bless and Rage, you will be +5% to hit and +90% damage. Shackles of Pain is one of the best ways to help kill boss mobs as it applies all of the damage you take to them as well. Expect to die using it. But the good new is, when you are raised from the dead, you can apply it again as all your Skills reset. When combined with the Talent Morning Person, which allows you to be raised with full health, this is a devastating combination. All of the other Man-at-Arms skills are very useful as well. Be sure to get Battering Ram, Crushing Fist, Rage, Helping Hand, Cure Wounds and Whirlwind.

Aerotheurge: 1 (1 point)
Only 1 point is necessary in Aero, but do not underestimate the importance of this Ability. These are critical skills: Teleport & Wind of Change (Removes Petrified, Slow or Stunned). Teleportation is incredibly powerful and has a ton of uses (send strong enemies away, bring weak enemies closer, drop barrels on enemies, toss your companion Source-Hunter over obstacles, etc.). Wind removes statuses from allies is critical, especially in the late game. I recommend Thunder Jump for the 3rd Skill because having mutliple ways to move around the battlefield is important.

Hydromancer: 1 (1 point)
You only need this for Regeneration. Freezing Touch is nice to have in the early game and Slow is always a good debuff.

Pyrokinetic: 4 (10 points)

See the Pyro breakdown for details.

Geomancer: 1 (1 point)
Necessary for the very good Novice skills: Summon Spider, Bless, Fortify. This gives you your first summoned ally which is significantly helpful at all stages of the game, but especially early. Don't go any further in this tree as the Skills require too much investment in Geomancer in order to be any good.

Witchcraft: 5 (15 points)

See the Witchcraft breakdown for details.

Scoundrel: 1
This is necessary for two skills: Winged Feet and Fast Track. Fast track is a Haste skill that gives you an additional 2AP. Winged Feet lets you walk over surfaces, like lava, without taking damage, which is essential for some puzzles in the game. Adreneline is a decent 3rd skill to take (it should be called Credit Card).

Bodybuilding: 1
You need a point in this for the Talent "Morning Person", which allows you to be resurrected at full health by a companion.

With these Ability points in mind, lets see how it adds up:

2-handed: 2 => 3 points
Armor: 3 -> 6
Aero: 1 => 1
Hydro: 1 => 1
Pyro: 4 => 10
Geo: 1 => 1
Witchcraft: 5 => 15
Scoundrel: 1 => 1
Man-at-Arms: 5 => 15
Bodybuilding => 1

Total Points: 54

This build also works very, very well as a Lone Wolf build if you're going for the achievement. The explanations for skills are in the other sections of this guide, so I'll just keep this lean and to-the-numbers. Basically, we're adding points to two Skills: 2-Handed (for increased critical chance and damage) and Hydro (for some decent Adept Skills).

A level-20 Lone Wolf character at the end of the game will have earned 73 Ability points to spend.

• 68 points from leveling
  
• +2 points from the Talent All Skilled Up
  
• +3 points from the Ability book sold by the Seller of Secrets

Total points: 73

Here's your final Abilities, along with recommended Skills

2-Handed: 5 (15-points)

Three points higher than a Regular build. 25% Critical Chance and 300% Critical Damage.

Armor: 3 (6-points)

Same as the Regular build. Will give you access to dropped/sold armor that requires Armor Specialist 3, generally as good as it gets. If you're at the end of the game and don't need the extra point for some great armor, keep Armor Specialist at 2 and put the extra points into Willpower.

Man-At-Arms: 5 (15-points)

Aerotheurge: 1 (1-point)

Hydromancer: 3 (6-points)

Gives you access to a couple nice Adept Skils, like Water of Life and Cleansing Water.

Pyrokinetic: 5 (15-points)

Geomancer: 1 (1-point)

Witchcraft: 5 (15-points)

Bodybuilding: 1 (1-point)

Scoundrel: 1 (1-point)

2-handed: 5 => 15 points
Armor: 3 => 6 points
Man-at-Arms: 5 => 15 points
Aero: 1 => 1 point
Hydro: 2 => 3 points
Pyro: 5 => 15 points
Geo: 1 => 1 points
Witchcraft: 5 => 15 points
Scoundrel: 1 => 1 point
Bodybuilding => 1 point

Total Points: 73

With Lone Wolf we're maxing out three sets of Abilities:

• Man-at-Arms
  
• Two-handed
  
• Witchcraft

You are a force to be reckoned with.

Pyro Skills are one of your two main Skill Trees, so we'll go over the Skill choices in detail.

Pyrokinetic: 4 (10-points)

Novice

1. Burning Touch - Great early in the game.
   
2. Flare - Great early in the game (ranged)
   
3. Wildfire - This is your haste spell. Costs 4AP, but will cost you 3 because you'll be standing in fire.
   
4. Self-Immolation - Creates a fire surface around you. Your team will often catch fire if they're standing close to you, but that's the price you pay. This spell does give everyone around you +25% fire resist, however, so it will help against subsequent fire damage. This should be your first fire spell cast so that all others receive -1AP cost.
   
5. Firefly - Lets you draw a fire surface. It's not quite a wall of fire, but it's the next best thing, as enemies caught in it will burn, and they'll waste time trying to walk around it.
   
6. Avatar of Fire - Prevents Burning and adds fire resistance.

Adept

1. Fireball - This is one of the reasons we're doing this build: to cause damage with fire. You'll use this a lot.
   
2. Explode. Does damage to everyone around you.
   
3. Purifying Fire - Removes Burning, Frozen, Stun, Charm, Healing and Shields. You want to have spells like this handy to help allies.
   
4. Smokescreen - This is one of the most helpful spells for solving Guardian Statue puzzles and for stopping ranged attackers (if they can't see you, that can't shoot at you).

Master

1. Meteor Shower - This is the big boy and the only Master worth getting in this tree (the others due paltry damage by comparison). Set it down on a cluster of enemies and watch them die. This is the reason for this build. You should pull this off every battle. Side note: Have companions use Teleport to make sure all your enemies get clustered together before pulling this off. Maximize the damage.

Witchcraft Skills are the other of your two main Skill Trees, so we'll go over the Skill choices in detail.

Witchcraft: 5 (15-points)

Novice

There are only four Novice-level skills we really care about, so feel free to choose whatever you want for the final two selections. You may or may not make use of them (I don't).

1. Oath of Desecration - +40% bonus to melee damage. With your 2-hander, this is great. Especially works well with Flurry later on.
   
2. Malediction- Curse/Weaken enemies. Cast it on melee enemies who are close and giving you trouble.
   
3. Vampiric Touch - You'll have Regeneration from the Hydro school (5AP), but this costs only 4AP (3AP if you're standing in blood). Having 3AP Skills to fire off after peforming major actions makes this build versatile and powerful.
   
4. Summon Undead Warrior - One of the main reasons to take Witchcraft is so we can summon undead. Having summons really helps when you are faced with a lot of enemies. It helps even the odds for you and provides some damage sinks for enemy fire.
   
5. Your choice
   
6. Your choice

Adept

1. Drain Willpower - Debuffs enemy WILL by -5, which allows the following spell to always hit.
   
2. Rapture - Charms enemies. With Drain Willpower this will always hit. A great two-turn combo is to (1) Summon Undead and then (2) Drain/Charm an enemy. Now your Battlemage has turned one character into three. Do not underestimate the power of Charm; there is no faster way for Death Knights (once made vulnerable) to be destroyed than for them to whack at each other.
   
3. Destroy Summon - This gets more powerful later in the game when boss mobs and other enemies start summoning allies.
   
4. Summon Armoured Undead Decapitator - Our second summons. He costs more, but he's worth it. His regular attack can knockdown enemies (especially good against casters without Bodybuilding) and he can taunt, which when successful can draw enemies to him, buying you and your team time to launch devastating attacks.

Master

Witchcraft has the best selection of Master Skills available; I seriously cannot decide each play-through which ones to take. But there is on that stands above them all... Invulnerable.

1. Invulnerability - This is a must-have skill, especially in the late game. Being able to turn invulnerable for 2 turns is awesome. It is especially helpful against Death Knights, but also very effective at saving your bacon (Honour Mode play).
   
2. Death Punch - This Skill scales with INT and level. It also does crushing damage which many creatures are vulnerable to. It won't do more damage than a critical hit with your weapon, but given the derth of 2-handed crushing weapons in the game, and the prevalence of enemies with a weakness to crushing damage, this is a good damage-dealing Skill to have.

A Note on Invulnerability: You will need an INT score of 13 in order for Invulnerability to have a 100% success rate. At INT=12 you will have 90% success rate, but it will feel more like a 10% success rate. So don't chance it - get your INT score to 13. It is very easy to get your score to 13 with equipment. You want to have a 100% chance of success with this spell because you'll more than likely be using it in critical situations and having it fail to apply really sucks.

Also, keep in mind that Invulnerable removes all buffs. So, if you have Oath of Desecration, Bless and Rage active, you should swing your weapon first and then apply Invulnerable at the end of your turn.

A Note on Soulsap: It may seem tempting to take this Skill, and it is awesome (especially against boss mobs). And since you will have Drain Willpower you can make sure Soulsap lands. However, as a damage-dealing Battlemage, I find it is better to give Soulsap to one of the other squishies in the party, like an Elemental Mage, than to have the Battlemage use it. That said, if your Battlemage is the only character in your party capable of taking Master level Witchcraft spells, then take Soulsap instead of Death Punch. You'll want it for boss fights.

You'll receive 7 Talent points by the end of the game, at level 20. I will show you both builds (Regular and Lone Wolf)

Regular Build

• Starting: Opportunist
  
• Starting: Know-It-All. Grants you an extra INT at the expense of reputation. Your other Source-Hunter character should do the talking (and preferably have Leadership anyway)
  
• All Skilled Up. Available at level 3 and really helps you get out of the gate fast so you can get a "1" in most abilities quickly and get your virsatility working.
  
• Elemental Affinity. This is what this whole build is based around.
  
• Morning Person. The whole reason we put a point into Bodybuilding was so we could take this Talent. It is awesome. By the time you get to your 5th Talent selection, you're going to want this.
  
• Bigger & Better. Gets you another Attribute point.
  
• Demon. More fire resist. By level 15 you should be healing when standing in fire.

Alternate: If you have enough Fire Resists by the time you take your final talents and do not need Demon, then I recommend Picture of Health, which only requires Man-at-Arms 2, which will grant you bonus hit points (and bonus hit points are never a bad thing). You could, alternatively, take Leech, which heals you while standing in blood, however, since I have no personally played with it I cannot verify its usefulness. That said, there's a lot of blood on the ground in the last quarter of the game.


Lone Wolf

• Starting: Lone Wolf
  
• Starting: Opportunist
  
• All Skilled Up.
  
• Elemental Affinity.
  
• Morning Person.
  
• Bigger & Better.
  
• Know-It-All.

With Lone Wolf we're sacrificing the Demon Talent. We're losing 15% Fire Resist. You just have to make it up with equipment (which is not that difficult to do).

While our long-term focus is Pyro and Witchcraft, those are actually not the most useful skills to have at the beginning of the game. Thus, I recommend the following starting Abilities and Skills

Abilities

• Two-Handed
  
• Man-at-Arms
  
• Bodybuilding
  
• Aero
  
• Hydro

Skills

• Battering Ram (Man-at-Arms)
  
• Teleportation (Aero)
  
• Regeneration (Hydro)

Battering Ram is a great way to get some ability to move around the battlefield quickly. Very useful early in the game and you will still use it in the late game. Being able to move rapidly across the battlefield (and knocking down enemies) is a great starting skill.

Regeneration really needs no justification. You'll use it all game long and it's necessary early. Every party member should have it.

Teleportation is a really useful Skill for solving puzzles and managing the battlefield. In the early part of the game you'll be using it to pull squishy enemies (especially Clerics, Priests and others who will resurrect fallen enemies) closer to you so you can kill them off. This is why Opportunist is so important as well; the squishy types will try and flee from you when you pull them within melee reange, and quite often your attack of opportunity will finish them off.

The tactics for this build will change as you gain levels, Abilities and memorize Skill books.

In the beginning you will be a versatile Battle-mage; more battle than mage, using your melee weapon to kill enemies and your Skills to buff yourself and allies. You will heal, teleport and manage the battlefield with CC spells. Early on you'll make use of the touch spells like Freezing Touch and Burning Touch.

By the time you get Fireball, you want to have the Elemental Affinity Talent and you want to start acting more like a Pyro-Battlemage. You'll use Self-Immolation to give yourself a firey surface to stand on and then you'll start casting your fire spells at enemies and following up with melee attacks on anyone that gets too close. You'll use Battering Ram and Thunder Jump to run around the battlefield casting Explode and firing off Whirlwind attacks. Use potions to heal yourself (2AP). You will start to be the force of nature that this build allows.

Late game is when it gets really fun: You will get Meteor Shower at level 15. Then the real devastation begins. You won't be able to launch this spell at the start of combat (due to AP cost), but you can pull it off 2nd or 3rd turn, depending on how you set it up. Getting it off early is not important - hitting as many enemies as possible is.

Sequences

Success in combat often depends on being able to think a couple turns ahead. Planning your attacks and combinations can help you launch the really devastating stuff.

More importantly, coordination with companions is key. Sure, you will have access to all the spells you need, but casting them all yourself takes turns and AP. It is far more efficient if your companions also have some spells to help you out and support your build. For instance, I like to make sure that my party Wizard has spells to help me be an awesome Pryo-Battlemage and to protect the other members of my party. So he has Avatar of Fire (which he'll cast on my Knight, who is most likely to get burned while engaging in melee combat) and he'll have Wildfire (to cast on me) so I don't have to waste AP casting it on myself. He'll also have 4 Ability points in Pyro so he can also have access to Fireball and Meteor Shower. "First rule in government spending. Why build one when you can have two for twice the price?" Two Meteor Showers is extra-awesome.

With that in mind, here are some turn sequences I use with this build.

Summoning
If I am facing a lot of enemies at once, my party will spend the first turn summoning. This means spiders, Nick and undead. For my Battlemage that usually means Summon Undead Warrior and not the decapitator, because it's less AP and he's just going to die as a meat shield anyway. That gives me some AP left first turn to either cast Self-Immolation (fire surface) or Wildfire (haste). Enemies will take their turn attacking the summoned creatures. Second turn I'll drop Meteor Shower on them and the world will be set ablaze. Third turn, standing in fire, I'll be launching the rest of my fire arsenal. Fourth turn I may need to Thunder Jump or Battering Ram and then Explode.

Fire Spells
Before you start launching Fireball, Explode and Meteor Shower, you want to Self-Immolate and give yourself a fire surface to stand on (if the enemy hasn't lit you up already). It is best to hit as many enemies with Meteor Shower as possible, so before you launch it you want to have other party members use Teleportation to gather enemies to a central area. When everything is on fire and your AP is reduced for all fire spells, you'll find that you usually don't even have enough fire spells to use up all your AP.

Witchcraft
When you get your Adept Witchcraft spells, you can start to Drain Willpower and Charm enemies. This is a great way to turn the numbers in your favor. This is usually a 2nd-turn tactic for me. First turn I'll summon an Undead Warrior while my party summons, and then I'll find an enemy to drain and charm. Let then do some damage to their allies. The Charm will wear off in 2 turns, which gives me time to prep fire and Meteor Shower.

Companions
Your companions are going to catch fire with this build. It is just going to happen. I highly recommend that if you have a melee character in your group (and you should; Knights rule) then give them good resist gear, like yourself, so they can wander the battlefield unscathed. In the early levels, I usually cast Avatar of Fire on my Knight so they can wander into battle and not take so much fire damage.

With Summons, Charm, Man-At-Arms attacks and Fire spells (especially Meteor Shower) you will do great amounts of damage during the course of a game. Acquire Fire Resist gear for you and the melee fighters and you will love this build.