I suggest using:
3 Crimson Archon Shards with ability strength (so we [Reach] 95% slow Gloom) (at least 1 needs to be Tauforged (unless you use [Power Drift] instead of [Catapult], in that case you could also use only 2 shards for ability strength and the rest 3 for ability duration)))
2 Crimsom Archon Shards with ability duration (to improve 2 buff time, Gloom drain and 4 drain)

With Gloom, if your HP runs out and you throw out the enemies, it will instantly heal you fully which makes you basically unkillable as long as you have enemies in stomach and Gloom is up.

MODS:
[Brief Respite] for shield gating (take note of only 75 base shield)

Arcane Blessing or Molt Augmented.

Enjoy!