I suggest using Crimson Archon Shards with ability strength for even more Mesmer Skin etc.

1. Cast Mind Control over an enemy.
2. Hit the enemy with radiation (not needed, but makes other enemies able to damage him as well) + make it take some nice damage.
3. Cast Enthrall on that enemy. (this can be done WHILE shooting since Enthrall is a one-handed ability.)
4. You now have an unkillable thrall that will keep brainwashing other units for you. (which makes [Thrall Pact] stay active with barely any effort)
   (Also keep 2 up at all times)

Abilities:
With both Enthrall and Mind Control you can have an invincible ally, which is what this build is focused around. Also we dont really need duration without his 4, which allows us to slot that augment instead.

Normally the thralls will die really fast, especially if you play with other people. But thanks to Mind Control you will have 1 invincible thrall that will just keep going around and inflicting enemies to become allies (so they are harmless and help you) for 68 seconds. Even though the other thralls die, this one will keep making new ones.

We removed ability 4 (spin to win :( sad to remove) because it will kill the bonus thralls anyways, and this build is about controlling puppets. The first thrall you make will continue to make puppets, and using 4 would just get the killed, rendering this playstyle less useful.

Mods:
Streamline or Mind Freak

IF YOU DONT CARE ABOUT USING REAVE AND JUST WANT AN ARMY FOR THRALL PACT OR LOW-LEVEL MISSIONS TO AFK WITH (Also to keep that [Thrall Pact] damage up):
Use [Narrow Minded] instead of [Stretch], then forma the slot with a Vazarin symbol (you also use Vazarin symbol there in my other build) This will allow you to have 68 seconds of uptime on Enthrall and Mind Control (instead of the current 38 seconds). I honestly think this is the best army ability, yes, better than [Nekros].

[Thrall Pact] will grant you about 500% bonus damage to primaries. If you just want to focus on the army, you could swap it out for [Mind Freak]. However I think this option is FAR superior (but if you dont use a primary, are farming xp or just want to use abilities, its a bit pointless)

No [Vitality] mod since you get survival from Mesmer Skin which scales with ability strength.

Not many tend to mod for duration, but it benefits 2 stun time and greatly helps the energy cost on other abilities (also usability on 1), it heavily benefits 4 since you dont need cast the ability and charge up a new puppet often.

Arcanes:
Molt Augmented for more Ability Strength throughout the level. (Also when your Mind Controlled/Enthralled enemies kill enemies, you still gain Molt Augmented stacks EVEN if you didnt hit the enemies lmao)

WEAPONS:
Use a radiation gun to proc radiation after using Mind Control, so the controlled enemy will take damage from all sources and get a massive boost. I suggest my secondary: Nukor Primer Since it has Radiation innate damage and high status chance.

FOCUS SCHOOL:
VAZARIN for protective sling when recasting Mesmer Skin.

If you want to use this with my other build Spin to Win Sentient Powers Revenant Prime You would need to use an umbral forma at [Umbral Intensify] slot. Then have a Vazarin slot (downwards pointing triangle) at the [Stretch] location and at [Mind Freak] location.

Video Showcase

Enjoy!