In the old basic Dungeons and Dragons set there were 4 paths to godhood. The most interesting one was the Path of the Polymath. Basically, the character had to advance to level 36 (max level) as a Fighter, then they were magically reverted to 0-level where they could once more advance, but as a Cleric, then a Thief, and then a Mage. Their memories are removed each time, being restored to them when they meet the conditions for the Path each time.
Adapting this idea, the 30th level characters sitting around the portal could well be on the cusp of godhood, reliving the memories of multiple lives adventuring. Or it might well be a single person standing there at the portal, with the bending of time...his entire advanturing party was just alternate versions of himself! His face altered, his memories changed slightly to accommodate the twisted path he has followed. This could be the big reveal at the end, as the alternate paths merge at the end.
Just a thought.
Adapting this idea, the 30th level characters sitting around the portal could well be on the cusp of godhood, reliving the memories of multiple lives adventuring. Or it might well be a single person standing there at the portal, with the bending of time...his entire advanturing party was just alternate versions of himself! His face altered, his memories changed slightly to accommodate the twisted path he has followed. This could be the big reveal at the end, as the alternate paths merge at the end.
Just a thought.