This tileset was the third one I've ever made, and also the latest. It's a sewer tileset, and in a style that isn't very Knytt-like, but meshes well with the other sets I made, which include Beatific Halls (a series of opulent galleries with coloured tapestries and giant golden balls and chains everywhere), a temple, and a basic ice world.
I hereby donate these tiles (all posted in this thread) to the community to be used in any way seen fit, including but not limited to changing individual pixels, colour/tone changing, and cutting upping (to make CO's etc). All I ask is that I'm credited for the work somewhere within your project.
I only have this one on my memory stick, more to follow
Also, feel free to constructively critique! These were made a fair time ago as you can see, but soon, I'll be making tilesets for my next project, and I want to do my own spin on the Knytt style. So tips etc are very welcome!