Metagross is one of my favorite pokémon ever, so yeah, I'm biased.
It is also one of the best in terms of tanking hits and hitting hard,
and would defeat Hydreigon in a fight.no because hydreigon is an special attacker and I keep forgetting that
Though I do like Hydreigon a bit (yet I preffer its preevolutions)... But still, Metagross is by far my prefference.
Amusingly enough, for some reason when I first saw it I thought the Deino line was a dragon/grass type, a type convination I've been looking forward forever. I just thought they looked like some weird purple plant.