Changes

Wyverns speak Draconic, but usually don’t bother with anything more elaborate than a loud hiss or a deep-throated growl much like that of a bull alligator.

Wyverns are rather stupid but always aggressive: They attack nearly anything that isn’t obviously more powerful than themselves. A wyvern dives from the air, snatching the opponent with its talons and stinging it to death. A wyvern can slash with its talons only when making a flyby attack.