@Raoul: This portal is by far the most powerful spell effect Raoul has ever seen... It seems to be a permanent, one-way portal through time, as he of course knew before jumping through it. The surprising thing is that instead of being made into an item, as is typical with permanent portals, this is just a free-standing effect, as if it were created by a spell. You expect that the spell is drawing on so much magical energy just to continue to function, that it is actually
causing the dead-magic zone around it. There simply is no more magical energy to be tapped nearby it, because the portal is using every possible "drop" that's available.
You wonder if a moral being could ever create something that powerful, or even any outsider you've heard of, other than a deity. You've heard of custom dweomers beyond the kin of normal mortal magic which can involve tremendous sacrifices on the part of the casters. It might be possible, in theory, to create something like this effect using one of those, but the cost to the caster would be immense... at least his life, and maybe his very soul. Or maybe even the lives and/or souls of a great many sacrifices...
Raoul also observes that this side of the portal seems to be "stationary" in time, while the other side "ages" normally. That is, no matter at what time-point creatures go into the portal in the "future", they all seem to be coming out at pretty much this exact time in the past, hence why there are so many very fresh bodies here... These people all just came out of the portal in the last few minutes or seconds (and then died horribly almost immediately...). There is probably a bit of "drag" for the time the portal is fixed at in the past, otherwise they'd have all came out at
exactly the same time, which would have been... messy. He estimates that this end of the portal probably "ages" less than a minute for every 100 years that passes. Which means that in the "future", no one has entered the portal for years after you guys did (since no one has came out after you).
@Marlowe:He knows everything in
their stat block. It just looks like there is a crazy huge swarm of hellwasps (game-mechanically it is a bunch of
different, individual swarms, of course). Their stats are the same as the ones in the SRD. Which basically means you guys are fucked if you can't get out of here fairly quickly, since you have no means to harm them at all in a DMZ.
You've heard of a layer of the Abyss that is basically just filled with demonic insects and insect-like demons, with hives of these things the size of small mountains. Perhaps someone opened a Gate to one of those nearby...
edit: and with that kids, I'm off to bed. have fun storming the castle!