This game is very good. But it's hard to know what you're doing at first since too many enemies spawn and cramped together and I didn't know that they drop something. Also is there a way to heal? and does the tree drop something when you kill it?
There is a ability when you inflict burn, you have 0.5% chance to heal 1 HP. If you have a great rate of fire with burn damage, this is basically vampiric damage and you become almost invincible.
I was able to destroy a tree and it doesn't drop anything. Very sad :(