A fun game, impressive job animating all this, it all of it looks really nice!
As others mentioned, balance is a bit off, I spammed heavy attacks until I found Tentacle Garden at which point I spammed that until I won. But that's hard to work out in a game jam.
I really liked the idea of becoming corrupted to exchange power, it works out into a really interesting system. In a larger game, with ways to remove corruption, it would make the game a really interesting tug-of-war as you balance out your corruption vs. your strength. A fantastic idea!