i don't think this is a repost, but if it is just trash it.
i was playing on mirandaswow when i saw a player one shotting everyone with ice lance. i asked him how much dmg he was doing and after a minute or so he said he was getting about 20mill crits. i asked him how and after a few minutes he told me that if you enter and exit karahzan 90 times then kill something outside of karahzan(most likely the bug goes away if you don't kill a mob) you'll be getting 20 mill crits.
i thought it was worth a try so i went and tried it out. the glitch worked perfectly.
ill get a picture for you all here soon but right now the server i normally play on is down.(this is for private servers)
update: I screwed around with it last night and varying numbers of entry's. i went until my spell dmg started to decline then i stopped. i was at like a couple hundred thousand spell dmg when i got these results.you need to kill anything before you get a loading screen.
and for all of you flaming me i apologize this is my first post. i do realize this is a repost on stacking but for those of you who's server took precautions to stop stacking using items this could be another way to accomplish the bug.