Those of Madness...

http://images4.wikia.nocookie.net/__cb20080830124038/wowwiki/images/thumb/6/63/Spell_misc_emotionangry.png/85px-Spell_misc_emotionangry.png	Seek madness... Or obtained all the Madness Weapons of the Plateau of Madness.	50
You have to obtain all the Madness Weapons.
Category:Plateau of Madness achievements