1 here is the wyverns wing hand joint the wing claw hand is able completely rotate around to allow the wyvern to climb up cliffs that they tend to live in
2 the wyverns tooth is hollow and pointed much like a medical needle able to injuct venom or acid
3 here is the wyverns snake like tongue and the hidden nozzle underneath that allows the wyvern to "Spit" acid over a distance
4 the wyverns foot like its hand has sharp long claws for digging into stone
5 the long tube to the nozzle under the tongue to the wyverns stomach the source of his acid spit the tube stomach and mouth are in impervious to the acid
of course there is the wyverns sting that works much like a scorpions and is deadly killing most anything with a single sting