Created basic sprite. I'm going to modify it a bit.

Got the rooms to pretty much snake along.

As I expected, sprite-based tiles look a hundred times better than those plain, blurry black lines I had before. The visual style has nothing in common with what I had in mind at the start, but I'm kind of exploring ATM.
Who knows what's gonna come next.

Began reworking the half-assed collision system. Still needs work, which is set for tomorrow.