Elona Shooter. It's basically a jrpg with guns instead of swords and endless swarms instead of turn-based combat. it's so random that one day you'll get a wave if mice to headshot xp farm and then the next you get a wave of tanks, ogres, flying dragons laser dragons and bosses with fify bagillion life that all your allies like to poke the shield of so damn futilely. and ontop of the sheer relience of an rng to dictate difficulty, if you dont get a decent manual reloading gun or a freaking rocket launcher, you're screwed, and will die aggravatingly 4 seconds before victory. about 98 times. before you hire a mercenary who drains money from you like some kind of leech, where you will be left owing like 5000000 dollars to the angry debtors of the village you're defending.
This is on easy mode too. with all the "make enemies suck" mods active. hardcore mode is determined to rip your balls off by day 4.