Frenzyheart Brew
Sold by Ripe Disgusting Jar. I don't know about the rest of you, but I'm really waiting for a dancing animation for this.
Frenzyheart Brew is a toy obtained from the 
Ripe Disgusting Jar, which can be purchased from the Frenzyheart tribe vendor at Revered reputation during the Wrath of the Lich King expansion.
Guide awaiting review
Reach Revered With Frenzyheart
Earn Revered reputation with the Frenzyheart tribe to unlock access to their vendor, where you can purchase the Ripe Disgusting Jar.
Open Jars For The Brew
Purchase the Ripe Disgusting Jar from the Frenzyheart vendor and open it — the Frenzyheart Brew is one of the possible outcomes. On use, it transforms you into a Wolvar for 5 minutes and is not consumed upon use.
Tips
The Frenzyheart Brew is not guaranteed from every Ripe Disgusting Jar, as it is one of several possible outcomes.
