A really cool variation of the Collapse mechanic with this survivor theme AND gameplay! I really want more development of it, I think that a upgrade shop and some achievements (like Drawkanoid or Vampire Survivors) would be really nice to improve and bring more content to the table.
I've a feedback about the falling magma punitive dynamics: losing a column AND a life AND having even more magma in you is too much. Maybe focusing in just one (like losing columns) and going for high score would give a more pleasant experience.