Cause they're weak against it. And wyvern is another word for dragon
not true cause a wyvern walks on 2 legs and a dragon(fatalis, lao) walk on 4 legs.
Get armor with good defense on dragon + fire then get a drag attribute sword like Obelion or something. Also bring your own potions, barrel bombs, and any other stuff to help u. And everything depends on strategy. Wish ya luck! ....(youre gonna need it)
i thought they were wyverens? so y would u use dragon attribute?
Well, some wyverns are weak agaisnt dragon.
But I thought S.Rathlos and G.Rathian were BOTH weak to Thunder?