Dark Portal Failure

[Shade]

So...have been playing a lot of corruptors lately, and I've noticed that on rare occasion the Dark Portal spell will inexplicably fail. Without being under the effects of confusion, antimagic interference or anything of the sort. Would anyone be able to tell me why? Has resulted in at least one death so far.

[Mewtarthio]

Could it be that you were in a no-teleport area, such as inside a vault?

[Shade]

I'm quite sure I was not.

[Tharsonius]

enemy teleport immunity? just a guess

[Shade]

Hmm...would that prevent the corruptor from moving?

[Tharsonius]

yea the spell will fizzle. i know from wearing rod of sarillion and corruptors trying to portal me, but i dont know which enemys actually have teleport immunity since i dont have much experience with corruptors myself