Berserking

This enchant increases attackpower by 400 and lowers armor by 5% for 15 secs, same procrate as mongoose and executioner, double stacks as well for 800 ap and -10%

The glow of this enchant is similar to Savagery(the red bleeding animation, but appears to show stronger on onehanders for some reason).

The effect is a bloodlust sound and the "enrage" animation.

I guess the reason they added the armor debuff is so that tanks cannot gain such a strong buff without being punished:) as well as you'll need to get hurt to berserk!.

And regarding joeythebull's reply: Alot of high end recipes is purchasable by the <Shard Trader> in Dalaran next to the Enchanting Trainer, each of the green recipes costs 4 Dream Shards which is the WotLK equivalent to Large Prismatic Shards and the Blue recipes including this one is sold for 10 Dream Shards.

Edit: Added the 3.0.8 change where the armor penalty was reduced to 5% instead of 25%, this change was mainly introduced due to warriors not benefitting enough from it because of Armored to the Teeth, which increases attackpower by armor value.

No DK's will be using this enchant, they'll be rather using Rune of the Fallen Crusader.

Massacre is 2h only. While Titan's Grip applies, you should specify you are referring to it, since some will assume otherwise.