One of the rewards for WAR's Daemonic Gifts of Khorne event is a scroll that turns you into a Flesh Hound. It isn't just for show, as you get a whole new set of abilities to use. There are actually 3 scrolls you can choose from, the other two being a Bloodletter and Juggernaut.
Here are the hounds abilities...
The abilities do not do much in the way of damage, but the effects are very nice. Crush Hands cuts the targets outgoing damage by 50%. Bloodthirsty Howl is an AoE Action Point Drain. Savage Lunge is a knockdown. All very useful.
And, of course, a video!