Registeel

Clear Body
Stops the enemy from lowering this Pokémon's stats.
Type Tier
Steel BL
Statistics
Min- Min Max Max+
HP
80
- 301 364 -
Atk
75
167 186 249 273
Def
150
302 336 399 438
SpA
75
167 186 249 273
SpD
150
302 336 399 438
Spe
50
122 136 199 218
Name Item Nature

Rest-talker

Leftovers Careful
Moveset EVs
~ Rest
~ Sleep Talk
~ Toxic
~ Seismic Toss / Earthquake
252 HP / 236 SpD / 20 Spe

Max HP, as usual, and give it a ton of Special Defense. Seismic Toss is generally better than Earthquake, but Earthquake can be used to hit Steels and Poisons, who are immune to Toxic, Super Effective. However, Skarmory and Weezing are immune to EQ, and Steelix and Forretress take more from Seismic Toss, anyway. The real reason to use Earthquake, however, is to let Registeel take on Substitute Jirachi. You'll need about 100 Attack EVs or so to break a defensive Jirachi's Substitute. Earthquake also beats Raikou faster, with Toxic taking care of any Reflect Raikou you see. With 100 Attack EVs, Earthquake will 2HKO Raikou, also, as long as Sand Stream is in play. Earthquake will also stop any annoying Magneton you encounter. Seismic Toss is needed to defeat Substitute Zapdos, however, so it's a trade off.

This only works well as a Special Tank on a team with Tyranitar, in general.

Name Item Nature

Curse

Leftovers Careful
Moveset EVs
~ Hidden Power Steel / Rock Slide
~ Earthquake
~ Rest
~ Curse
252 HP / 160 Atk / 96 SpD

Its defenses are already great so it can really take a beating while it's Cursing up and then Rest off the damage. Of course, typical phazers like Skarmory and Suicune will Roar / Whirlwind this away with ease.

Name Item Nature

Starter

Leftovers Impish
Moveset EVs
~ Thunder Wave / Counter
~ Earthquake
~ Rock Slide / Hidden Power Steel
~ Rest
252 HP / 88 Atk / 16 Def / 152 SpD

This moveset is for a Registeel lead. It works well against some common leads like Aerodactyl and Zapdos. Registeel has immense defensive stats, so even Choice Band-wielding Aerodactyl will surely lose. Thunder Wave is very annoying and Rest keeps you in the game. If you use Hidden Power Steel over Rock Slide, you may run into difficulty with starters such as Substitute Zapdos.

Name Item Nature

Choice Band

Choice Band Careful / Adamant
Moveset EVs
~ Superpower
~ Rock Slide / Hidden Power Rock
~ Earthquake
~ Explosion
252 HP / 252 Atk / 4 SpD

Official Registeel Choice Band moveset. The only move you might actually hurt something with is Explosion, though, but if they have Skarmory you're still in deep trouble. Registeel just lacks attack power. Hidden Power Steel can go on there somewhere, but its only purpose is to have a safe move, to damage everything equally (i.e. not at all), instead of predicting with other moves.

Regirock is generally superior for this, due to its higher Attack stat, but Registeel has the advantage of being able to take Water attacks. Unfortunately, Registeel won't be beating those Waters it can switch into, thus making that mostly irrelevant. This makes Toxic a better option than you'd think, as you can just Toxic that Suicune, Vaporeon, or Milotic that thinks it can switch into you safely once they know you're a Choice Bander (even Milotic doesn't like Toxic), and then just beat them down with one of your other moves later.

Other Options

Thunder and Thunderbolt are Registeel's only realistic options of dealing with Skarmory coming in on him so easily. Registeel can use Zap Cannon to Paralyze foes and do some damage, and has the defenses to be able to use a few of them if it misses.

EVs

Depending on what set you choose, you'll probably want some defenses, mainly. The Choice Band moveset should obviously have 252 Attack EVs. Registeel is slow so you probably won't be out-speeding anyone. Max HP on Registeel before even thinking about touching those defenses, though, because his HP is so low compared to them.

Opinion

Registeel is too easily beaten by many other standards. It lacks a lot of attack power, so the only way it can beat something is with Explosion. However, since Skarmory is one of the main counters this too isn't very effective. Registeel just really shouldn't be used in standard, and it's too good for UU.

However, Registeel does fairly well in the uber metagame. It takes Special attacks like nothing, and can easily Curse up to beat them one on one (use Hidden Power Ghost in the Cursing set). It resists Hidden Power Flying and Meteor Mash, two big threats Ubers have a hard time taking. It can Explode on Groudon or some other big threat you can't take out. Registeel's attacks are fairly weak early on, so it has a hard time taking out its counters.

With few exceptions, Toxic is the only way Registeel is going to hurt something.

Counters

Skarmory, Weezing and other tanks that can (pseudo) haze and absorb physical damage. Metagross, Swampert and others using STAB super effective moves will easily tear through it.

In Ubers, beware of Groudon and Rayquaza. Kyogre can be a bit of a problem, Reflect / Whirlwind Lugia as well.