Are that person who posted those tile set/mockups on Pixelation recently? That thread closed a few days after being posted, and these are reminiscent of them.
Want to give some dough back to all those amazing pixel artists? Donations provide prize money for contests, help cover hosting costs and support new initiatives.
@christoballs that wasn't me
@sturmgewehrkreuz that's half on purpose - certain tiles only appear in proximity to bullets (so its like the bullet is lighting up the cave i guess)