A pretty old glitch, as far as I know this hasn't been leaked yet, but I guess it's good to promote ezud with as this is just a graphical bug.
The bug itself is pretty famous, lots of videos on youtube about it, you used to be able to just walk away with the crate, but that was fixed, soon after that you were able to poison yourself and teleport away with a ring of life, that is also fixed, the only way to do it now is as following.
The original box noob:
A poser doing the glitch:
The crate is a part of the
Death to the Dorgeshuun quest. How you do it:[HIDE=5000000]Edited out the way to do it.
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If you and the other person dress exactly the same, this bug can cause alot of mayhem, alot of people will follow you and report you, even though it is graphical, watch out when you do it.
Good luck! ^^