Hariyama. Seriously. Hariyama is a bloody beast, really. Base 144 HP? Yes please. Along with Base 120 Attack, which is WELL above average, Hariyama's got the power to stay and kill. Hariyama's movepool is also Grade A material. Pretty much every Physical move you could ever want. BUT, on top of that, Hariyama also gets Knock Off and Whirlwind. Both of those moves are awesome in standard play, and Hariyama gets them. Tell me it's not cool to have a Pokémon that can knock the Leftovers off a Blissey and OHKO it right afterward with a STAB Focus Punch. Is there really anything more you could ask for with this titan?
Hariyama's neglected in this Poll, too. I'm the first to vote for him, for one thing. And, when Deathskully went on about STAB Focus Punches, he didn't even mention Hariyama. I seriously fail to understand why Hariyama isn't used more. I, for one, find a Pokémon that can mercilessly kill while simultaneously being a pain in the arse to take down incredibly cool.
Blissey's a nuisance to defeat, but it lacks the offense to do any really damage. Same for Skarmory. But Hariyama, with its enormous Base HP and two weaknesses, resists Attacks from BOTH sides of the Attack Spectrum, and it deals back damage with a Base 120 Attack.
And that's not even mentioning Counter, which is just too bloody good on Hariyama with that titanic Base HP. And Guts. Really, as if Hariyama wasn't enough of a butcher with its other statistics, they went and pumped it up with Guts. So, let's think. Base 120 Attack + STAB + 4 different weaknesses to Fghting(Ice, Rock, Steel, Dark) + Guts + CB = Kill, absolute kill. Barely anything is going to live through that.
Thick Fat is also a great option on Hariyama. While you won't get that boost to Attack from Guts, it cerainly makes Hariyama a nuisance to kill(as if it weren't already). This beast just wins on so many levels that I have to marvel at the fact that I never see it in OU.
Heracross has that nice Bug STAB, yeah, but it doesn't have the durability of Hariyama(Heracross, BTW, having only 5 more Base Attack than Hariyama

). Heracross certainly can live through attacks(I've yet to OHKO a Heracross with an unboosted Psychic from my Celebi on NB), but Hariyama is difficult to kill on a totally different level.
~*CB*~
The 8th Champion