I've gotten a lot of help from the folks on Discord on all aspects of this class, but I gotta give credit to Cobramax76 for the major tip on the Lasguns.

The reason we're going with Lasguns is their "Rate of Fire" (RoF).

Shields aren't an issue at all, Shield Piercing: Ignores the target's shields.

We'll be putting in a little Suppression damage too. But we don't need much.

This build is hot right out of the gates. It just gets stronger as the fight continues because we will be utilizing "Debuff Stacking".

There is no need to build or maintain tokens of any kind.
Debuff stacks apply at an insane rate.
It's good for high density mobs and Boss kills.
It does not rely on "Auramancy".
It does not rely on crits.
It does not rely on Morality or Seasonal specific gear. There's only one Ancient Relic(Belt) that I would consider critical and the two Signums.
Works on every enemy type.

You'll want five summoning slots and use an Alpha summoning weapon in the fist slot. So you'll need a Technomartyr Vestment and Technomartyr girdle. We'll go over detailed gear selection later.

Slot 1: Kataphron Vanguard equipped with the Power Axe
The Vanguard will draw attention away from your Combustors. Even though they will regen health quite well, you still don't want them drawing a lot of attention.

Function: Crowd control, Debuff application
Debuffs applied: Shock and Slow
Effects: Taunt, Knockdown/Knockback (damage mitigation)
Modules: Two Forcefield and one Endurance
% Supreme Damage Reduction, % Physical Resistance, % Damage Reduction and % Heat Resistance seem to be the best. Wouldn't hurt to have % Warp Resistance in there too, but you don't run into that damage type as often.
You want him to "soak" damage and keep the enemies focused on him as much as possible away from your Combustors.
It's all about damage mitigation and survival, but I have one set to trigger a Fabricatus Scatter Field. I've heard the complaints. For some it crashes the game. But it doesn't for me. And the Knockdown/Knock back effect is great damage mitigation for the tank and adds a little DPS into the crowd. I'm not ditching such a great feature.

This is mostly a single player game. The crash seems to mostly apply to co-op missions. So just keep a decent module in storage to swap out for that one with the Fabricatus Scatter Field if you are running missions with friends. On a co-op, you won't really need the extra damage mitigation.

Slots 2, 3 and 4: Psiloi Combustors equipped with Las guns
The Mechasapient perk will give you nine on the battlefield. I know you're thinking you could run more, but trust me, nine is plenty. It actually works better this way.

Function: Damage
Debuffs applied: Hallucination
Modules: All Offensor
Primary Enchant: % Damage for every Debuff on the target with one exception. On one of them, only one, put a chance to cause Hallucination on it.
Other Enchants:
% Damage against Burning enemies is your best enchant. It offers the highest percentage.
I know what first comes to mind: "Lasguns don't apply Burn!". Well...... yes they can. We will cover that in the TA's gear later in this guide.
% bonus for Ranged, Heat and Damage all have about the same percentage of boost. So all are good. And slide in a % Life Drain for Ranged Skills on one or two modules when you get some decent four slotters for added survivability.

They will die if they take some of the direct heavy hits, but they can sit in a poison pool or fire patch and DPS through the damage.

Slot 5: Kastelan Robot equipped with Phosphor Cannon and Flamer
I know Kastelans aren't premium DPS generators, but that's not his job. He's going to help with debuff application and does a decent job of clearing out those nasty enemies that get stuck in cover that the Combustors can't seem to get to.

Your primary weapon is going to be a Plasma Cavalier Beta in the second slot. And this is why the Kastelan is great in slot 5. He's maintenance free. Is he gonna blow up in some of the really tough fights? Well yup! But you don't have to worry about tabbing over to re-summon him. He'll reboot and get back in the fight soon enough.

Function: Damage, Debuff application, Clearing stuck enemies and to some degree, crowd control.
Debuffs applied: Shock, Burn, Poison and Bleed.
Modules: Two Offensor and one Forecefield
On the Offensors: % to Poison on one, % to Bleed on the other. % Damage against Burning enemies, % Life Drain for Ranged Skills and +HP on hit if you have four slotters.
On the Forcefield: % Supreme Damage Reduction, % Physical Resistance, % Damage Reduction and % Heat Resistance.

Kastelans don't do spectacular damage. You just want him to stay alive as long as possible to keep spreading debuffs. But I have noticed, when he gets up to a nice, gathered, high density mob and rips the Flamethrower....... LOTS of health bars drop!

And you'll also note I put "crowd control" in his list of functions. He will work as a second Tank, but since he's not another Vanguard, it doesn't interfere with the Vanguard's Taunt Rate. In many cases he'll go in to draw fire before the Vanguard does, and he'll also tank flanking mobs that come in from the sides to keep them off of your Combustors.

As I've run this build for a good while now, the Kastelan seems less worried about protecting you and more concerned about protecting the Combustors. Which is exactly what you want.

He will also tend to get stuck behind the Combustors in tight spaces. You can get next to him and kind of push him around to free him up, but don't worry too much about it if he's stuck. He'll keep shooting the Phosphor Cannon and Flame Burst from range into the mobs. And if stuff slips past the Vanguard and starts coming for the Combustors in large numbers, they will get a face full of the Flamethrower.

Mechasapient - You Teleport in an extra Psioli Combustor
The obvious first choice because that gives you the nine Combustors.

Electro-Scourge - +2% Movement and Attack Speed to Constructs for every existing Construct.
We're taking advantage of the Combustor's RoF and will have eleven Constructs on the field most of the time. So let's just make them fire even faster......

It doesn't hurt to increase the rate for the Vanguard and Kastelan as they cycle through their attacks either.

Persistent Attrition - Enemies affected by DoTs are Blinded as well
We're debuff stacking. This is a free debuff and the perk makes it ignore the Suppression check. This is why you skip the passive skill point in the passives to make the Lasguns do the Blind.

Now, the Constructs didn't used to be able to apply this, but something changed. They do now. And in the TA's gear we will be spreading Burn quickly and to multiple targets at once.

Logic: 25 points
You will be summoning them to refill the ranks, recharge your shield and for the damage buff.

Bionics: 15 points
You really don't want Aegis Protocol in this build.

Mindlink: 15 points
Good overall cool down and survivability.

You are going to focus on Construct Offense and Defense with plenty left over for a little resilience from splash damage for the TA.

Construct Defense(Benedictions of Omniscience)
26 points.
We don't need anything that helps the Tarantula Turrets, Knockdown isn't a real issue and the Combustors are still kinda squishy, you don't want Strain Transfer redirecting any damage to them. So no need to waste the points. You won't really be taking that much damage directly on the TA anyhow.

Construct Offense(Anathemas of Omniscience)
24 points.
We're not using Phosphorus Barrage or Destroyers.

Construct Ability(Technoacheology)
15 points.
Pretty self explanatory. No need to waste points to try and open up Relentless Constructs. With all the other recharge rate in the build they will be easy to keep summoning.

Construct Specialization(Forge Mastery)
14 points.
Again, don't worry about Focused Beams. We have an easier way to apply the Blind without a Suppression check.

TA Survivability:

Support(Hospitaller Curia Doctrines)
5 points.
Lower right-hand corner. Get the four Skill Cool downs and Invigorating Faith.

Damage over Time(Venemum Toxin Mastery)
3 points to unlock Fast Metabolism

Health(Magos Biologis Secrets)
8 points.
Upper right-hand corner. Unlock all the maximum HP and Neural Rewiring

Defense(Secutarii Seige Axioms)
14 points.
Left column, Physical Resistance: four points, straight up.
Center column, Heat Resistance: six points, all the Heat Resistance and the shield booster(Runic Wards)
Right Column, Warp Resistance: four points to open up Shock Dampening

With recent changes it appears that a lot of simple debuffs that were only able to be applied by the TA have been given to the Constructs as well. As mentioned with the perk Enhanced Attrition, if they apply the Burn, they also apply the Blind.

Constructs don't crit. So avoid any debuff applications that require it and enchants that have the words "skill hit" in it. Everything shown applies to the constructs. I haven't tested all the possibilities, but for this build, I don't need to.

What I have tested:

You can stack Enrage and Berserk tokens with construct kills, but it does NOT enhance construct damage. So it's pointless.

The six slot shock explosion PCD does NOT apply to the constructs. Kinda bummed about that one, but they can't make it too OP.

Weapons:

The cornerstone of this build is the weapons and enchants on it. I'll have the Plasma Cavalier in the image. That goes in slot two. In slot one, I have an Alpha Axe. Both are just standard Relics because that's where the primary enchant you need is available. The only difference between them is that the Axe has the fire aura on it. The build does not rely on it, but it's handy to use the fire aura to dissable traps I can't shoot. The enchants will be the same so that the Constructs will continue at 90% DPS while I'm knocking out a trap skull.

I also know which weapon is equipped. You need the Plasma Cavalier Beta to direct the constructs.
But the Kastelan in slot five won't summon if the Alpha weapon isn't in slot one.

SLOT 2: Plasma Cavalier Beta
The two enchants of major importance are the Primary enchant: All Construct Heat attacks apply Burn on Hit with a 15% chance.
Now..... the Lasguns can apply Burn! 15% might not seem all that great, but their RoF is just insane, so everything gonna BURN!
And the Psalm Code Doctrine: Applying a Burn Effect on an enemy also applies Burn on enemies in a 5-meter radius.
Spread the love....... the hot.... burny love.......

All the rest is just to boost either the Combustor's Lasgun itself, or all the Construct's Heat and Ranged damage.

There will be cool down reduction in several places in this build to help keep all the Constructs up for overall damage and RoF from Electro-Scourge.

Psalm Code Doctrine: Applying a Burn effect on an enemy also applies Burn on enemies in a 5-meter radius.
X1 Shard: Fulgurite

SLOT1: Either A Voltaic Axe ALPHA or an Omnissian Axe ALPHA.
It doesn't matter, whichever one of those you get with more enchant slots and higher levels.
Try to match up the same enchants as the Plasma Cavalier as best you can. You won't use it often.

Psalm Code Doctrine: Fire Aura.

Signums
Adds Heat Vulnerability on causing a Burn effect
% chance to add a general Vulnerability when the target gets a debuff effect

The one I have only has 28%. It comes with better than that, you just can't change it. But with the RoF on the Lasguns, both Heat and General go to a solid ten stack if the enemy last more than a second under direct fire.

The rest is self explanatory. Boost the Construct's damage, recharge rate and you can slip in a little loot quality if you want.

Put your best Signums on the Plasma Cavalier and do your best to mirror it on the Axe. But the ones on the Axe aren't critical.

Armor
I just like The Technomartyr Vestment of Leadership.
One of my Combustor trios is getting a damage boost. This is also available on a standard Relic. I'm Radical, but I'm sure for Puritan having the immunity to DoTs would be nice. That would also give you three more Passive points to play around with. You will occasionally take damage and get a DoT on you, but I'm mitigating that a bit from Fast Metabolism.

There were a few primary enchants that looked good that you can play with. The armour isn't a critical piece. Just resilience effects for you or the constructs. Just make sure they can trigger the effect.

Psalm Code Doctrine: 125% Heat Damage Bonus, Affects Constructs
Shards: X2 Corpus Shards to boost your health pool for the random hit you don't dodge in time.

Belt
Technomartyr Girdle of Calculation
You won't get much out of the Shield drain. Unless you gotta Switch to the Alpha weapon and run to catch a Wandering Servoskull or bolt to an information hunt operative before they kill it. You're not built for face tanking. Go easy on the Tarot card level bumping for just those missions.

But you will be maintaining your Combustors, and you will be able to summon them a lot. If your shield is less than capped, just summon something even if all the constructs are up. Summoning them is still giving them a 10% damage boost. So sometimes you summon them when you are full up on bots.

Shards: X2 Fulgurite Shards to boost your shields for the random hit you don't dodge in time.

Eye Implant, Neural Implant and Purity Seal should all be making sense now. Cater to the constructs and their buffs.

Main Implant
You can run the Main Implant of Boiling if you have a good one, but I can get better stats out of a standard Relic. The Primary enchants to choose from on this piece aren't spectacular, and not critical either. Constructs don't apply heavy damage DoTs, but the % Damage bonus for Burning effects will bump em up a few points. More damage is more damage.

I tested "Hitting an enemy affected by Burn has a 5% chance to deal 100% of the original hit’s damage in a small area, applying Burn". We're already spreading Burn all over the place, and even with their RoF, I wasn't impressed.

Psalm Code Doctrine: 70% Heat Damage Bonus, Affects Constructs

Innoculator
Just pick something that helps keep you alive when everything goes haywire. It'll happen. You'll be running because you got a bit cocky and they wipe your Constructs.

Psalm Code Doctrine: 100% HP to Constructs

Totals on the important buffs:

111% Ranged Damaged Bonus for Constructs from TA gear

68% Damage Bonus to the Las guns from TA gear

216% Heat Damage Bonus for Constructs from TA gear
195% Heat Damage Bonus from Psalm Code Doctrines(Affects Constructs)
That's 411%, not including the bonus you will get from the Offensor Modues.

140% Damage Bonus for Constructs against Burning Enemies from TA gear.
Not including the bonus you get from Offensor Modules.

As far as gear farming goes, getting good Offensor Modules is your bane. The drop rate SUCKS! I had to put in a lot of hours and run a lot of Void Crusades to get my collection. We'll add up the additional modifiers from each cluster of Combustors and show some totals from the TA's gear.

Combustors Slot 1:
Base Damage 1068. (50% = 534 per shot)
81% Damage for every Debuff on the target.
178% Damage Bonus against Burning enemies. 318% total.
43% Heat Damage Bonus. 454% total.
120% Damage Bonus.
104% Life Drain for Ranged Skills. 124% total including passives.

Combustors Slot 2:
Base Damage 1064.(50% = 532 per shot)
57% Damage for every Debuff on the target.
46% chance to cause Hallucination on hit.
174% Damage Bonus against Burning enemies. 314% total.
34% Heat Damage Bonus. 445% total.
39% Damage Bonus.
149% Life Drain for Ranged Skills. 169% total including passives.

Combustors Slot 3:
I put my best Modules here.
Base Damage 1071. (50% = 535.5 per shot)
87% Damage for every Debuff on the target.
187% Damage Bonus against Burning enemies. 327% total.
83% Heat Damage Bonus. 494% total.
45% Damage Bonus.
104% Life Drain for Ranged Skills. 124% total including passives.

And I'm sure the math on some of that is low because you also have to factor in the 111% Ranged Damage for Constructs and 68% Damage Bonus to the Las guns from the TA's gear. But you get the jist....... Not even going to total up the damage for the Kastelan, but he does add a nice bit to high density mobs.

We're buffing the damage output as much as we can to offset the -% Damage Dealt on higher leveled missions and it works. You can't even notice the RoF on level 100 missions because they one shot damn near everything. But run a level 117-118 Assassination run (the best Tech Fragment mission there is) or a 120+ Void Crusade mission and you'll really see it. The per hit damage is always going to vary based on Tarot card selection, but it's still savage.

This isn't a turn you Fire Aura on, run through the map, kill everything in your wake, face tanking, speed run build. It's a little slower paced.
But it is a kill everything build. And I've been running it on level 120+ missions since I got the Lasguns to level 100. The higher you get the Lasguns, the less you have to re-summon. And the higher you get the Lasguns..... more 120+ boss fights are doable.

You'll have to follow your Constructs around and use the Plasma Caliver to move them in the direction you want to attack.

You'll have to watch their icons and keep summoning them when they get picked off. They do like to go off on solo missions and pick fights with flanking enemy mobs. They're pretty good at handling a flanking group of enemies, but they will stir the hornet's nest at the most inappropriate times.

They can't shoot over rails, through sand dunes, through walls, etc....... Sometimes you have to wait till the Kataphron and Vanguard kill that one enemy stuck in cover that they are focus firing on dies. If you can sneak up the hill or into the room and summon at least one group of three, they'll clear it and you can move on.

Standard battle tactics are still your friend. Attack from the high ground whenever possible.

Stay clear of the "Combustor cluster". They will pull aggro from ranged enemies with nukes and sneaky off-screen Champion charges that'll kill the lot of them. If you're standing there, it's a one shot drop. So you will still have to maintain some mobility and spacial awareness.

If they all get hung up on a larger cluster of enemies on maps like Tropospheric Platform and can't hit them, simply retreat. The enemies will follow to an open firing range. Kill them there.

I really don't have a problem with any enemy type, but some I have to be quite mindful of. The Aldari Champions are brutal on the Combustors. Seem to kill them easier than most enemies. And they have a sweeping attack that has more range than most. It'll cut a path through your constructs and one shot you. So staying a bit farther back from the Combustor cluster is advised.

Let the Constructs do their thing for the most part. Yes, you will be using the Plasma Cavalier to move them in a certain direction, but if you target a nurgle in close proximity, they will ALL attack that. This can recall your tank that's keeping 50 enemies at long range right up in your face, and they're coming with him. Just fire at the ground in the direction you want them to engage. They will fire in multiple directions spreading the debuffs around faster.

I know that the Plasma Beam will increase your Construct's damage another 50%. And if you want to get clear of the Combustor cluster and channel on a Boss you can. But after a point you simply don't need to. They will easily kill it without your help after the Lasguns get leveled to 100. Then you just want to stay clear of splash damage, nukes and watch out for flanking mobs.

It sounds hard, but it's not. The bad scenarios are only about 1% of game play. Most of the time they just slaughter everything at an insane rate.