If you include insects and arthropods and everything suddenly turns into uberbloodlust-kill-all-humans then non-human animals win, hands down. I think people overestimate their ability, the effectiveness of weapons, and the sheer number of insects that are near you at all times. Insect biomass alone outstrips humans by an insane margin. Very few mammals or other animals would get a lick in, I think. There is no hermetically sealed bunker that would hold for long, and that won't save you from the mites already on your skin although they probably can't do a ton of a damage.