[@SoleAccord]

The draw-back I had in mind is that she would have to throw an special dagger to a place before teleporting to it. So the assassin throws it, it sticks in the wall and then she can teleport there. She'd have two of them. She could potentially stick on in the ground and teleport into it later, but I imagine the teleporter only has a limited ranger anyway.

Other than that, the assassin would just be a really skilled and stealthy fighter to be the tough boss fight.

EDIT: I thought about, and decides that it probably won't go faster than the average throw, too. Plus, I'm a Play-to-Lose kinda guy. I'm not gonna play to defeat you and I won't pull out any random "OH YEAH WELL" moments either. That stuffs just kinda silly. 

But I like the idea of it being hold her weight so she can stick to walls and ceilings, and climb them too. I just think that's neat and is a good way of her traversing from roof-top to roof-top or something like that.