Totally agree with jaranka. I don't allow Utility spells to be offensive.
bennis1980, I recommend that you have a talk with the guy. Let him know that Spell Type is going to be by the rules from now on.
"..only affect the caster, a willing target, or a target incapable of resistance." If target is KO'd or completely bound (you could kill them anyway), I allow it. Other GM's may not
or just give a +100RR.
Otherwise, as soon as you guys sit down for the next game, ask them to make a RR. If they fail, then make them roll their own Impact crit from "as high up in the air as possible". Tell them (or not) there was an invisible Mage casting Teleport from the bushes... Why yes, he has been studying the exact spot 3 miles above the ground so that he's familiar with the teleport location.
In other words, do they want it to happen to them! Goose/Gander
Even if they get skilled enough to Spell Master or use Arcane or whatever- and make the spell offensive, it's now a Force spell, which would get a RR. But both of those options are dang risky.
Summoner's have
Teleportal in their Base List. This is a F spell (RR) and the higher level versions
can make you be sucked through a portal but the destination is within 10' of the caster and they must have cast a previous spell just to get a "lock" on you. Still not a good offensive spell.
Now you could try to Spell Master a Telekinesis to increase the max weight, but it would be costly, risky, slow, require concentration (50%Act) and they'd still get an RR. I give Demons in my world juiced up Telekinesis. They like throwing objects (like people) into walls. But you still get an RR.
OR have the player use Spell Research to make a new offensive F type of Teleport/Leaving spell. No, on second thought, don't give them any ideas.