Cave Story Critter Tower Defense - Sacred Grounds
[From the credits.txt]
Credit to the following contributors to Critter TD;
Noxid, GirakaCHEEZER, RunLancer etc for Assembly Compendium & Functions List
Wistil for Cave Editor
zxin for being a slave driver
gamemanj for PEONS
And most obviously, Pixel.
Cool Video, Man.