Acquire the Brewfest beers listed below. Don't drink them all at once!
Note: This achievement was removed as a criterion of Brewmaster in Patch 3.3.0.
Your character will need to be at least level 65 in order to earn this achievement because of Ogre Mead and Mudder's Milk. Apparently, I misunderstood the new tooltip: you need only purchase the items; you do not need to actually consume them.
For Horde players, see Strange Brew.