So I tried the portals out a bit on a local save. The wierd thing is I seem to never be able to get back through the same portal I entered! When I go back into the portal in the hell dimension I end up in some other portal (than the one I entered through) in the real world. Does this always happen or am I just unlucky?
I destroyed one portal I got through in the real world, and it just resulted in me teleporting to yet another portal the next time I teleported from hell
Results in a lot of involuntary spelunking for my part as the new portals are always inside huge cave systems
If there are a lot of portals around the one I created I guess it's not impossible I end up in one of those instead and I have to destroy a couple until I have only my portal left as a destination. But if unlucky the game will always create other portals than the one I entered through, which results in a pretty useless travelling system.