Samir
Explorer
It's a free action with no trigger ("As a free action, you can teleport a creature within the zone 3 squares" has no trigger), thus it can be done as many times as necessary. Ordinarily this wouldn't be an issue, because the zone is only 1 square big, so (under normal use) at most you can teleport one creature per turn--unless you're teleporting that creature up, in which case it lands in the same square, taking falling damage and letting you do it to him again.... So we're pretty much settled on this, then? Its a free action with a trigger, so its only going to happen to each creature once