A solid roguelike drilling game. The upgrade system is definitely a nice touch. It took me so many tries to be able to afford even the first improvement, though.
The unexplained-ness of the void works well. It is inexplicable, yet insatiable. It did catch me a lot of times even when I didn't hit any oil or bombs.
The font is a bit hard to read. Many times letters smear into each other. Kerning is your friend, even (or perhaps especially) at this scale.
And I did notice too many colors on the upgrade screen. The greying-out of unaffordable options seems to push over the four-color limit there. Without that misstep, the rest seemed to fit four colors just fine.