Well our guild killed Rumblecrush tonight. After no one wanting the mask, I looted it. Oddly from no mask to wearing the mask my AC went up 60! I have no idea how any of the formulas work, but it was a huge incriment in my opinion. Anyways, perhaps there's just an error in the graphic profile.
I doubt that. I will take a guess at why. When a character has under seventyfive(75)agi, there is a significant AC penalty envolved. For example, when my shaman was younger and I had trouble staying above 75agi(ogre with fungi) I went from around 1000 to 880. Check again what your agi is before and after you use this and see if I am correct or not. If i am correct, you need to make it priority to get your agi over 75 especially if you are of the level that is able to kill rumblecrush.
i had an acumen mask and a gold diamond mask, the latter which i wore during raids for its resists. With this mask my stats fall between the two. I can have stats and resists in one...For my wizard this certainly is an upgrade. Yea not great, but it certainly can be of some use for some. my 2cp
I agree that this isn't all that great for the risk involved. However, if you are killing Rumblecrush, you are doing it for the possibility that he will drop something better. Mobs can't drop uber items every time they are killed.
Unlike most of the drops from Rumblecrush (the BP drops, notably), this mask rates as "total crap".
While this item would certainly have some use if it were off a more accessible target, like the Hive Fiend, Shadowy Assassin, or even Zelnithak, putting this item on Rumblecrush does little but waste a chance for one of his better drops.