Methods I've been able to recreate this/notes about the problem:
Wormhole: if you "cast" teleport as the worm hole CD is ending and get the animation of casting, but do not move, once teleport is available it will fire off sending you backwards. This problem is worsened with the passive [Illusionist] since if you're struck and the teleport skill resets it sends you sailing back into the mob you just escaped.
Illusionist: even without wormhole I've had this proc and send me backwards a few times, however much less common without wormhole than with it.
I have come across the same issue. After casting the first two teleports and attempting to cast the third, the character will do the spell cast animation, but the spell will not work. Seems to happen if the teleport is cast as the cool down initiates. As soon as the cool down finishes, the spell takes effect and the caster is teleported and the cool down begins again. I've had all of the following scenarios occur with the third teleport:
1) Nothing happens (I saw the third cast animation, but when the cool down finished, nothing happened, and cool down did not initiate)
2) Teleports ahead as if I had just cast teleport
3) Teleports for zero distance
4) Teleports backwards as if I had just cast teleport
5) Teleports and puts me where I would have been if the third teleport had actually cast correctly
6) Teleports backwards some X amount. I've gone many different distances on this one, but never further than where I would have been if the third teleport had cast correctly.
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