First, I must say that I need of find a proper location to make some of my projekts. Kaktocity will be like... a tempate
Piece of Nether: A location (a cave, but I'm thinking in a ravine) covered in netherrack. It will have lava, (nether mobs would be ideal, but theres no safe way to do it, so...) glowstone, quartz ore and netherish things...
CorruptChunks: Sum selected chunks that I will turn in Nether-like (obviously, only in the surface)