A short but sweet game. With solid graphics and music that feel right at home on Game Boy. Digging dirt and using the jetpack was fun too (using the jetpack underground digs above you, which is handy). I always thought that the dirt you dig up was converted into gold but your interpretation is pretty good.
Though, I feel the upgrades were pretty standard and I would've liked a secondary goal like finding machine parts to be used alongside gold to fix the ship. What we have is good but a its loop feels a bit repetitive. Also an in-game explanation on how to change tools would be appreciated.
Overwise, good game. I'll miss the moles, too.
You can play my forgetful goldfish game, if you like.