Congrats, here are my remarks.

The good

• simple mechanics, cool concept
• movement feels alright
• graphics are coherent
• music is not bad
• theme works well

Area of improvement

• unfair / no feedback: when lava rises, it’s not intuitive or noted in any way that the goal is to climb on top of those falling rocks
• the gameplay feels too random: i had two situations where rocks fell too far apart, and when i stepped on one rock, another one fell on top of me

Overall, a solid entry, look out for linear increase of difficulty. Dying too many times at the beginning makes the game feel boring.