A fun little boss battler. I liked the varied abilities of the different slimes, and the phases of the bosses.
As some below mentioned, the poison one's range seemed to be a bit further than it looked; got caught out a few times in that one. And on that note: I was missing a lot of feedback in this; e.g. when I get hit, I sometimes don't realise it, and when I hit an enemy, there's very little indication that I did. The poison boss being pushed back is the only one (I think?) where there was a good indicator of that.
The weakest slime is actually pretty strong. They didn't even need to absorb the others, really. I eventually used the fire one to beat the lasers one because it gives me passive damage while I focus on dodging, but otherwise the original slime's dash attack seemed best!
Anyway, a cool game!