I like it so far, it's a promising demo! The pickaxe was a neat addition, not very many mario maps do that. Just a few things you should consider:
-the button you have to shoot to teleport took me a while to find, because I couldn't see it behind the flowers
-please hide the jump boost particles, they're distracting
-consider adding enemy spawners in certain areas of levels, so the game can be more challenging
-maybe a custom resource pack?
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