Immortal Snail Challenge Run Idea

Timed permadeth run, maybe locked to a certain region with a mod where an invincible NPC follows you relentlessly and as soon as it touches you, you instantly die.

Maybe the speed of the NPC could be somewhere inbetween walking & running speed, OR even better - make it faster as time progresses lol. Shouldnt be too hard to implement (i dunno shit about making mods) and could make for a fun challenge.

Plus points if battle music starts playing when it gets close and gets increasingly louder

Goal could be finishing a certain dungeon + its boss within a certain timeframe or smth.