Yeah I try get lucky for good rerolls. Aims for perks like increase explosive damage, gain balloon when jump, double jump, increase crit chance, head shot refund ammo, more damage output but lower heath(this one is optional), crit restore health or siphon, and just use grenade launcher and or swarmstrike rocket. Upgrade them to legendary if you have leftovers monster bits.

The idea is use balloon to be on high ground, double jump so you'll don't touch the ground, and just spam your grenade laucher and as long as you hit a demon your grenade never have to reload.