Thread:Deathstalker666/@comment-1496755-20151224121621/@comment-1496755-20160404053451

It's a mixture of both, actually - I've read that he was eager to get back to the more humorous and light-hearted spirit of the Keen games and was not quite happy with the creative direction taken with Wolf 3D and later Doom.

Catacomb had exploding walls, which could conceal secret areas...