The best thing about this is the open issue claiming it's "Too much like the real Terraria source code." [1] :)
This bring back a lot of memories. Way, way back in the day i wrote a clone of Battle City [2] in XNA with a half-decent AI. I had intentions to learn and use some OOP patterns. I ended up with a handful of monstrous classes and generally a clusterfuck of spaghetti code. But... i learned a lot about AI and path searching algorithms and, best of all, it worked. I think i still have this code sitting on a disk somewhere. This makes me want to throw it on Github.
Thanks for sharing!