Tips and tricks to build:
Ancestor mod, you need a DEF on it. this build is make 210% DEF and have 324k DEF. so barely capped.
if you dont get 320k DEF, switch Shell Crusher to Annihilator modules. (auxilary and sensor and 2 bottom moving fortress)
Arche Tuning is made to Critical hit guns. slightly differend if using multi hit.
Guns:
Mobbing: Eraser
Wall Crasher: Thunder Cage good to go.
Abyss bosses:
use gun what abyss is weak to. but you ca make piercing light to Toxic. slight tip. so make few of those.
build itself, you can switch HP and Cooldown modules to other like "fire release" check leaderboard what other people doing it.
Skill Rotation (important)
1,2,3,4,1,2,3 in succession then hit a enemy with a skill then shoot it.
time to time (depents skill duration) you need to do 4,1,2,3 and hit enemy with a skill and then shoot it.
by hitting enemy in 1st skill renegates ammo per tick.
by adding "Compulsive impact/high-power rounds" modules to Eraser and piercing light, per tick you get even more ammo.
Ancestor mod:
for a good rolls, you need:
2+1 format. that can give even +200 DEF.
Priority:
DEF
good ot have:
Duration up or Range.
Duration makes skills last longer, and range... you know.
for a good negative:
shield
dimension (boost and modifier)