A nice addictive little game.
I like the eruption at the beginning of the game and the leaderboard was a nice touch. I really like how when lava or a fireball hit a cactus it felt nice and crunchy, something I found very satisfying.
I didn't find any "bugs" per se but I did find that using my mac the fireball controls felt unresponsive and almost random. I would also suggest adding some variation in the character jump sound as after a while it gets a tad annoying to hear.