Since it's a prototype, I didn't put much effort into graphics and sound - hence the visual atrociousness. The gameplay is pretty fun though - worth giving a go. I might consider making it into a full game at some point.
Move: WASD / arrows
Use selected weapon: Mouse
Select weapon quickslot: Number keys 1-5
Choose block for block placer: Click a block in inventory
Eat Shrimp Snax: Click it in the inventory
Load/save menu: Esc
Selling Copper Ore, Quartz Ore, and Gold Ore unlocks better drills and items, including a shrimp proximity zapper.
Discolored terrain blocks contain hidden items.
Gold Drill is the best.
There's a game-breaking reward at $2816.