A (almost) TC that follows the idea of making a series of small maps with a storyline about hellspawn and such (similar to doom2). It was supposed to follow the "classic" doom2 style gameplay, so it should feel like doom2.
Tons of people
New from scratch
Doom builder, Slade, SlumpEd, Zennode, Zdbsp
It says you found the secret level when you go to level 9/10