[Known] Grannus Colossus - gate issue in several places traps avatar

1. Title: Grannus Colossus - gate issue in several places traps avatar
2. Reproduction Rate: 20-50%?
3. Blocker? Possibly (avatar stuck unless use/stuck, or "start on world map")
4. Details: When I go to any part that has the "locked gates" mechanic where you're supposed to fight off waves of mobs, and I jump on a rock to lose aggro, or move backwards enough that a mobs aggro leash is extended to the point where mob runs back to his spawner, sometimes the mob that lost aggro on me turns into a mob that will no longer aggro, and is not able to be hit by avatars' attacks. I can not get out of the "pen" because I can't kill the last mob, and the game is stuck with me standing there. I can SOMETIMES get that last guy to be aggroable if I log out and back in, but that doesn't seem to be 100% either, so sometimes I have to lose all progress and /stuck, or start on world map, which is terrible.
5. Steps to Reproduce: Go to any part that has the "locked gates" mechanic where you're supposed to fight off waves of mobs. Have a bunch of guys aggro on you. Lose aggro on one or more mobs by running back far enough in the "pen" or by jumping up on rocks. Go try to kill the mobs again, and note if it is possible or not.
6. User Specs: not applicable

 

Bug #: 49354, thank you