Mistake on my end. A card is changed into one belonging to the creature that hit me. Still not sure what's causing the softlocks.
Edit: So as I mentioned, Gorgon stacks shields. I think those things are supposed to be gone the next turn (Slimes lose their shield stacks the next turn.) However, Gorgons have a tendency to add shields every turn. I've noticed that after enough shield stacks, the enemy skulls/runes disappear, and the end turn button doesn't work anymore.
There has also been some points in the game where no event card appears. I don't know what causes this to happen. I've been trying to see if I could change completely without being fully corrupted.