This would take the mod in a completely different direction than I want it to go, and would cause problems with pre-existing worlds.
Ok, well, thanks for responding!
One more idea, because it will bother me if I don't say it now. Traveling through portals takes you through the void into another dimension, right? What if portal travel came with a risk? (I swear, after this I will stop pestering you)
 
				
		
 It could be a lot simpler than you think. Any time a change in dimension occurs (only on single player, of course) there could be a chance of some encounter with the monster. Just so long as your code is open ended and only looks for a change in dimension, not a particular dimension ID.
 It could be a lot simpler than you think. Any time a change in dimension occurs (only on single player, of course) there could be a chance of some encounter with the monster. Just so long as your code is open ended and only looks for a change in dimension, not a particular dimension ID. 

