Exploitthe stage. Much like in Dark Souls, there are ways for you to exploit the geometry of the level to be able to land hits safely and cheese enemies- if you scope each arena out, you should be able to figure out where you can stand invulnerable from boss attacks, and use that to your advantage.
If you are playing the Steam or GoG version on PC, there are also these cheats (such as unlimited health), shown off in the video below, that you can try and utilize to have things go your way (a little bit). However please use this at your own discretion.
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