Smogon official tier: NU
Base Stats: 85 HP, 97 Atk, 66 Def, 105 SpA, 66 SpD, 65 Spe
Abilities: Gluttony, Flash Fire, White Smoke (HA)
Usable moves: Aerial Ace, Amnesia, Body Slam, Curse, Façade, Fire Blast, Fire Punch, Flamethrower, Focus Blast, Focus Punch, Frustration, Giga Drain, Heat Wave, Hidden Power (Electric, Fighting, Fire, Grass, Ice), Hone Claws, Knock Off, Low Kick, Night Slash, Protect, Pursuit, Rain Dance, Rest, Return, Shadow Claw, Sleep Talk, Solar Beam, Stockpile, Substitute, Sucker Punch, Sunny Day, Superpower, Taunt, Thunder Punch, Toxic, Will-O-Wisp
Heatmor is one of the unfortunate Pokémon to be categorized as slow and frail. You could say it’s like Seviper, only with slightly more bulk and better STAB. However, it does have two moves that give it a niche over other Fire-types: Sucker Punch and Giga Drain. The former makes it the only Fire-type besides Flareon to put a priority move to effective use, while the latter gives it a means to deal with Water-types like Seismitoad without the use of Hidden Power. It’s also the only Fire-type in the tier to learn Knock Off, although Sucker Punch is more preferable because of Heatmor’s sluggish Speed.
Heatmor @ Life Orb
Ability: Flash Fire
EVs: 180 Atk / 252 SpA / 76 Spe
– Fire Blast
– Giga Drain
– Focus Blast
– Sucker Punch
This set brings out the best in Heatmor’s potential, relying on its decent offensive stats and interesting movepool. Flash Fire is the preferred ability because White Smoke does nothing but prevent Sucker Punch from being weakened, which is pretty much only useful against Tauros. The Speed EVs serve to speed creep past uninvested Seismitoad, Special Attack EVs are maximized for optimal offensive prowess, and the rest is dumped into Attack. Rash vs. Mild is a matter of preference, and I just based the choice on Heatmor’s B/W analysis for lack of anything better. Fire Blast is its main STAB and is the 5th-hardest-hitting Fire Blast in the tier (behind Mega Camerupt, Magmortar, Pyroar, and Typhlosion). Giga Drain is, as mentioned, the niche of Heatmor, which allows it to hit Water- and Ground-types for nice damage and also recover HP lost from residual damage. Focus Blast is for hitting Normal-types and Rock-types harder than any of its other options; this is especially useful against Bastiodon and Probopass. Sucker Punch is a priority option to help its slow Speed and pick off faster threats that need KOing.
As mentioned, Knock Off can be used instead of Sucker Punch if you want to forego priority in favor of pure wallbreaking, although Fire Blast outdamages Knock Off by far. That seems to be the only other option, although if you want to go pure special, Hidden Power Electric is an option to destroy the likes of Pelipper and Swanna (although beware the latter because it outspeeds and OHKOs Heatmor).
http://pastebin.com/69PJRUpM (lacks hazards)