Judging from what we know of the foxes (Mat, Lanfear and Moiraine's experiences).

1. If possible, they would like to hold people prisoner. This is backed up by Mat's "wise to request leavetaking" or words to that effect, and Moiraine's still being kept captive there.

2. They can do weird stuff, involving past lives, the mind, the future, etc. Siphoning away part of someone's channeling power isn't much weirder than taking bits of people's memories.

3. Lanfear returned, as Cyndane in a new body. Moiraine did not.

4. We know that even if someone asks to escape Finnland, that doesn't mean they won't be killed first, like Mat (almost) was.


So, I've always assumed that when Lanfear and Moiraine went through the gate, they somehow put aside their fighting (or were forced to) long enough to get to the bargaining stage. Each of them requested 3 things. Lanfear was smart enough to ask for an escape, but was killed as well as being drained. Moiraine did NOT ask for an escape, perhaps because of her Rings and Min visions, which told her that she'd be rescued... probably.


Now, the only flaw in this is that Mat was only killed- he wasn't killed + something else, like Lanfear. However, we know that it's possible to "set a price," which Mat never did.

So, Lanfear totally could have said, "OK, I want this, this, and an escape, in exchange I'll give you a bit of my power." And the Finns went "sure... but also we'll kill you."

OR, Lanfear went "I want this, this and this, and in exchange you can kill me (the fools! they don't realize the Great Lord will ressurect me!)" and then the Finns played a little joke and killed her via draining her channeling or something.