WouW
Smash Lord
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#379 Registeel
Steel
Clear Body: Stats can't be lowered by the opponent
80HP/75Atk/150Def/75SpA/150SpD/50Spe
Sleep Talk
Registeel @ Leftovers
Clear Body/Relaxed
252HP/56Def/200SpD
Rest
Sleep Talk
Thunder
Ice Punch
With massive defenses and a lot of resistances Registeel won't have a lot of problems walling, although it lacks a recovery move, which is why Sleep Talk is used here. This can be used against Garchomp stuck on Outrage - with Adamant, Life Orb and a Swords Dance that doesn't even 2HKO, while Registeel does 2HKO with Ice Punch.
Registeel has rather bad offensive stats, so Toxic can be used, also to cripple switchins like Hippowdon.
Status
Registeel @ Leftovers
Clear Body/Impish
252HP/56Def/200SpD
Thunder Wave
Swagger
Iron Head
Substitute
This thing can really annoy the hell out of enemies, if they are confused with attack buffed, paralyzed and/or flinched. Enemies can really be annoyed if they get killed by confusion while being unable to attack due to paralysis or flinching.
Curse
Registeel @ Leftovers
Clear Body/Careful
252HP/4Atk/252SpD
Curse
Ice Punch
Earthquake
Explosion/Thunderpunch
With maxed Special Defense and boosted Defense it's safe to say that you're fairly sturdy. After a Curse Ice Punch OHKOs a Garchomp or Salamence while you survive anything they do - even a CB Garchomp's Earthquake. Earthquake can also hit hard after a Curse, and Explosion can hit really hard. Thunderpunch can be used for Gyarados.
StallSteel
written by Pink Reaper
Registeel@Leftovers
Impish/Clear Body
252Hp/56Defense/200SpDef
-Iron Head/Metal Claw
-Curse
-Amnesia
-Rest
Everyone tries it at least once, but the idea here is to forgo the much faster Iron Defense for the much more deadly Curse. Anyone dumb enough to let this set up will quickly find that after a few boosts, nothing can KO it. Iron Head after a few curses will put a big dent in anything. If you succeed in setting up and your opponent doesn't have a phazer or you already KO'd it, this pokemon will beat everything in the game bar none.
Metal Claw can be used for PP stalling.
Other options:
Aerial Ace if you know that your friend has a Breloom and a Heracross. Otherwise just don't use it. Iron Defense or Amnesia can be used for specialized walling. Counter on the Curse Set if you play in Ubers. Toxic can also be used on a support set.
EVs:
Relaxed/Impish with 252HP/56Def/200SpD gives balanced defenses, so you can take hits from both ends. The curse set specializes in Special Defense, as the regular Defense will be raised by Curse anyway.
Troublesome Pokémon:
Most Ground and Fighting types. Most Grounds will dislike Toxic though.
Written by WouW