Boars make supreme tanks, or used to anyway.
I think the initial AP boost from Charge used to affect Growl too, resulting in a massive initial threat spike on the boar. My 70 boar was getting about 4000 threat upfront which was hard to overtake.
I think Blizz tried to nerf this in the last patch, and I haven't played with my boar since then, so I don't know if they're worthwhile tanks anymore.
If I were multiboxing hunters, I'd have one good tanky pet and four good DPS pets - Boar+4xCats probably.
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