Originally Posted by Peelee
Originally Posted by Fyraltari
Spoiler: Dungeon Crawlin' Fools bonus strips
Xykon said "we" put the wooden doors over the entrance to keep zombies from wandering in. The then-current "Chief Gate Inspector" is also able to move towards a "purple swirly energy thing" through the gate before he's killed, so presumably the gate does function as a portal in some capacity.
My personal theory is that the Gates act as a sort of safety valve, diffusing whatever analog of pressure exists in transplanar physics; to both keep the existing rifts from growing and to mitigate the development of new rifts.