When cast at a creature the intended outcome is to send it to the temporal rift. (This is the location you get sent if you attempt to cast 930 without a familiar summoned) It would then be stuck there for whatever action RT it has for moving multipled by the average number of movements needed to leave a temporal rift. It's reappearance could then be anywhere in the vicinity, not necessarily the room it departed.
If you weren't successful at rifting the creature I envision a failure as being something like the gateways in WoT where the portal is still razor sharp and would slice arms/chest/head/neck with severed arms being the most likely location.
Additional usage would be for that of your hunting partner. If you witness them take a particularly nasty crit like a severed leg from a major ewave. You aren't in voln so you can't fog them, they're fairly big boned so you don't trust being able to prep 930, cast, drag friend mist, successfully. Simply banish them to a temporal rift to get a grip of themselves by prep 930, cast my friend. They can't cast in the rift but they can eat herbs or at least wait out the 12 round stun while you clear the room.
