In Elwynn Forest there is a spot high in the mountains with 26 sheep on a 4 minute respawn timer.
Be careful though. There is one sheep called Tekton that explodes and can throw you off the top of the cliff (to a squishy death below if you dont land in the water!). It only does 350 damage but has a rather large throwback effect.
I assume the sheep would give wool if skinned and also respawn faster.
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