Spoiler: screenshotsI made this over the course of... a while. it features a nice wave based progression system, which increases the number of monsters per wave as you go as well as the monster types, going from zeds, imps and pinkies to revenants, nobles, and archviles. it also changes the bonus loot you can get at the end of each wave.
Get the map here: https://github.com/Beelzebold/Beelzebub-s-Labyrinth
just keep in mind, UV is 4 times harder than ITYTD. so, if you're playing with a mod that makes the game a bit harder to play, well, tone the difficulty down.
(note: corpses don't disappear, so on lower end systems they may cause lag and will be hard to see through.)
music used is from freedoom 2.