The Daily Grind: Which patch would you like to see rolled back?

Usually, patches are nothing less than a reason to put on a gaudy party hat and boogie on down in celebration. After all, it's almost always good news, right? Bugs are squashed! Issues resolved! Features added! Content enriched! Classes balanced! Yet sometimes, a patch arrives that leaves a sour taste in one's mouth, as it does more damage than good -- it significantly weakens a class, it introduces a host of new bugs, it shifts the gameplay focus to an undesired area, or it trivializes past achievements.

So, assuming that you were granted the divine power to roll back one patch in one MMO -- a patch, mind you, not an expansion -- which would it be? Which patch still grates on your nerves to this very day, a patch so bad that you consider it an abomination to gaming everywhere? What one update to your MMO would have been better never being born in the first place? Speak your mind, or forever hold your peace!