It's simple, it's fun, and it's polished. I also love the detail of the monster's body adapting to the cards it's eaten!
One thing I will say though is that bomb cards not despawning means they build up over time. Obviously you want a difficulty curve somewhere but in theory this could result in the player having only bombs to pick from, which does kill the fun a bit. But for what you've got it's a fun game! Good work!