Gonna start off this comment by mentioning this: Drilly is so damn cute. Love the guy.
With that out of the way, let's talk about the rest of the game.
Gameplay wise, digging feels pretty good, but I sometimes had to wiggle into a good position before going back to mining because of the dig radius being small early game. Digging direction also feels rather limited, and it being downwards by default confused me a few times.
Graphics and animations are great! Definitely a lot of care put into it. Explosion effects and all.
Love how big some of the treasures are, like that old van and that Greek statue from dirt and stone layer respectively. Speaking of layers, the music and color palette changing accordingly to your current layer is such a nice touch!
A great entry! Just short enough to complete within 1 to 2 hours too.