Greatly varying difficulty between these heroes. The infinite life knight looks to be rather careful. The obvious way to kill him would be burying him alive or dunking him in a lava pit for extra sadism (in a way he can't crawl out). I'd probably burn Zombie girl? Need to know more about her ability. The psychic needs to be dealt with in a similar way to the Yakuza. The time stopper has to be ambushed before being able to react. Infinite leveling appears to be the last boss although he shouldn't really be that hard to dispose of.
Kuki ability still ???? But yo know honestly i thought about it but
Zombie is a kinda weird ability to have when i look at mr infinite lives and like huh
There are plenty of ways (admittedly difficult) to kill the reincarnates as long as she doesn't get exposed by the psychic (99999 lives = really hot mud bath).
And also, those two girls really need to follow OSHA guidelines about giant cauldrons full of biohazardous stuff.