User blog comment:Mckrongs/Monster Hunter 4 for the Nintendo 3DS/@comment-21378804-20131003110715/@comment-4212769-20131003131750

You can get Wyvern Gold from other Wyverns too so it has nothing to say about it.

I didn't think you would include Akantor/Ukanlos, however if you exclude them...

Well, I need to rethink something. Uragaan being very heavy because of the iron chunks and so on and it being longer (as seen on their pages) it could be heavier though because it isn't as compact as Gravios at this size they may have about the same weight.

Duramboros surely is heavy too, but the heaviest part is the tail (you can see as it uses it to catapult itself into the air). It has great fat reserves that make it heavy but I still think the armor of Gravios and iron chunks of Uragaan have more weight. And it is the smallest of these three. (Uragaan max size: 33m, Gravios max size: 30m, Duramboros max size: 26m)