[Aleph]

Returning to the original post, and taking a cue from another post on the top page.

2. Dreams of Rl'yeh has special uses against an enemy pretender, for when killing him just isn't enough (again, especially against immortal pretenders who aren't all that impressed by getting killed). You can use spells that age, curse, horror mark, or disease your opponent. Granted, you'll want your script to be something like "Horror Mark, Soul Slay" so that if you get a non-pretender you'll off them relatively quickly, but you can inflict severe nastiness on a pretender through Dreams. Remember too, that although Dreams allows an MR check to resist, once you're in it your MR is halved, so that horror mark is pretty much guaranteed to stick.

As you mention, it's also a much safer spell if they have astral mages. And, hey, if you know they don't have astral mages, then you also know they won't be casting Returning or Soul Slay on you while in Dreams, so you've got yourself a captive audience.