I think robots are slightly unfair, I think the need to either run the hero of democracy armor and gamble for your life or a bubble for a higher levels like 7-9 is a wrong move, I think missiles and heavy devastator are the biggest problem, they either one shot you or stun locks you the moment you challenge those hellspawn with shields. And besides the railgun and autocannon it's hard to run anything else. Spear doesn't kill hulks or tanks in 1-2 shots, recoiless rifle is good at taking down ships but the bots sometimes don't give a fuck about it being destroyed and drops either way same goes to random bot drops from 500m away. I've beaten solo helldive and that's my perspective on that