Battle Moveset

A Good Moveset for Registeel would have to be this:

Attacks:

Hidden Power [Steel] / Brick Break
Curse
Rest
Thunderbolt / Thunder

Or

Earthquake
Rock Slide / Hidden Power [Rock]
Curse
Rest

Items Attached:

Leftovers

Preferred Nature:

Careful (+Special Defence, -Special Attack) or Sassy (+Special Defence, -Speed)

Strategy Using Registeel

This is basically a physical version of Calm Mind Suicune. Much like Suicune, it has 580 Base stats and huge numbers in both defences. It has a respectable HP, a very nice tanking move set and has a huge number of resistances (including a resistance to Toxic) thanks to its classification as a pure Steel Type. It's ability somewhat lends to its Tank classification, however, from a competitive point of view, there are few Pokémon who will use stat-lowering moves so it is kind of wasted.

Once you've pulled off 1 or 2 Curses Earthquakes and Brick Breaks will pose no threat. The lack of popular Fire types out there means there are few STABed Fire Attacks to fear, and with the majority of Fire attacks being used as counters for Skarmory, they have little hope of succeeding in knocking out Registeel (even while it sleeps off Rest). Your best bet would be to switch into a Choice-Bander while it uses a 'Not-Very Effective' move, allowing you to have a free Curse that should give you the necessary protection against Earthquake.

The main issue here is losing Curses. Like all Pokémon who rely on stat boosting, it has problems with Hazers. The inclusion of Thunderbolt is to counter the ever popular Skarmory (who would also cause problems if your only offensive attack was HP Steel).

The first set is preferable to Metagame players, since they have easy access to HP Steel. It's a physical Suicune. Curse up a few times, Rest off lost HP then use HP Steel or Thunder/bolt.

This set is also usable to the non-Metagame, however due to Registeel's lack of STAB move, my suggested replacement for HP Steel is Brick Break, which covers similar types (however it leaves you exposed to Ghost types).

The second set is more of a Tank/Sweeper combination. HP Rock is the preferred replacement to Rock Slide since Registeel hasn't got the speed to take advantage of flinch, and, in this case it's Accuracy > Power. I wouldn't suggest Thunderbolt on this set since there isn't room for it. Just stick a Magneton on your team or find something else to counter Skarmory. Once there are no Hazers to stop you, Physical Walls don't pose a threat since you can sit there Cursing. There are only a handful of Pokémon capable of resisting both Earthquake and HP Rock/Slide, hence the combination.

In any of these sets, using Amnesia or Toxic/Thunder Wave could be considered, but I feel Toxi-stalling just takes too long to score a KO and is messed up too easily by Heal Bell or Rest while the bonus of Thunder Wave lowering Speed can't be capitalised on when using Curse. Iron Defence and Seismic Toss could be used in the 1st set in place of Curse and HP Steel/Brick Break but that is screwed up by 101 Subs and Pokémon with 301+ HP and a recovery move.

Registeel's only real fault is the fact that it relies on the opponent not having their Hazer left. By the time you've eliminated the Hazer the game can be won much quicker by sweeping than by Tanking. Unlike Suicune, sticking Skarmory in front of Registeel does cause problems and also, unlike Suicune, it can't force switches with Roar to take advantage of spikes and prevent Pokémon from setting up in front of it. Suicune is also twice as efficient at draining PP due to Pressure. Basically, it has 3 faults that make it a less efficient physical version of Suicune.

Other Optional Sets:

The Choice-Bander:
@Choice Band

Focus Punch/Thunderbolt/Thunder
Explosion
Rock Slide/HP Rock
Earthquake/HP Steel

Much like all Pokémon it can be a Choice-Bander, however a mediocre one at that. Its mass-resistances give it the ability to switch in easily. Focus Punch/Thunderbolt/Thunder allow it to counter the commonly used Skarmory, EQ/HP Steel and HP Rock/Slide cover the majority of types and Choice-Boom is just all-round fun when you are near to fainting.

The Skarm-Bliss Counter:
@Leftovers

Focus Punch
Substitute
Thunderbolt/Thunder
Ice Punch

Ice Punch is really included as a filler, mostly for the 'Bolt-Beam' effect and surprising Dragons.

The AI decimator:
@Leftovers/Chesto Berry/Lum Berry

Curse
Earthquake
Rock Slide
Explosion/Thunderbolt/Rest

Basically, your ingame Registeel. The AI won't haze away your Curses so getting 2-3 Curses off shouldn't be a problem. From there you can just sweep away and use a Hyper Potion whenever you get low on HP. Rest is an option for the Battle Tower and since this Registeel set is a Physical Sweeper (and not a Tank), Chesto-Rest is an option. Lum Berry sorts out any Burn or Paralysis issues and Leftovers is an option for obvious reasons.

EV Corner:

There are two preferable HP numbers. 301 (or 304) and 352:

- 301 allows it to take 3 Seismic Tosses before needing to use Rest (and 304 does the same except it works nicer with leftovers).
- 352 allows the maximum Leftover recovery.

Your choice depends on how many EVs you want to put in Defence.
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Metagame players should aim for a distribution like so:

{Careful} - 12 Speed or HP / 246 Defence / 252 Special Defence
{Careful} - 204 HP / 42 Defence / 12 Speed / 252 Special Defence

The minor Speed EVs give it a shot at outrunning other Pokémon with Base 50 Speed and few Speed EVs. Max Special Defence for absorbing Special Attacks and the rest in defence for absorbing pre-Curse Earthquakes.
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If you intend to use Thunderbolt, then the EVs need to be tweaked so that Thunderbolt will 2KO Skarmory.

{Sassy} - 12 HP / 30 Defence / 216 Special Attack / 252 Special Defence

Although it is rather costly as far as EVs go, it could be considered worthwhile since the ability to 2KO Skarmory is always favoured when using stat ups.
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If you want to save EVs (but risk missing) you could use Thunder, which is a lot easier to score a 2KO with.

{Sassy} - 12 HP / 246 Defence / 252 Special Defence
{Sassy} - 204 HP / 54 Defence / 252 Special Defence

As you can see, Registeel needs no Special Attack EVs to 2KO Skarmory with Thunder, however you run the risk of missing and therefore being forced to 3 or 4KO Skarmory (and lose the element of surprise).
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Non-Metagame players need to decide whether they want the Tank/Sweeper or the Tank.

- If using the Tank, aim to EV train HP, Defence and Special Defence.
- If using the Tank/Sweeper, aim to EV train HP, Attack and Special Defence.

Strategy Against Registeel

Since Registeel can take hits from both forms of offence with ease, the best way to go is super-effective attacks.
- With Physical Sweepers, you need to get off Earthquakes/Focus Punches quickly before it begins using Curse. Choice-Banders need to surprise Registeel as it switches in (since it obviously won't stay in against a CBer with obvious access to EQ).
- With Special Sweepers, you need to strike quickly. If you can't 2KO Registeel, just switch out to something that can Haze away Registeel's stat-ups.
- If you have a Pokémon with tough Defences and high HP, you should be able to sit there stat-upping as well.
- Resisting HP Steel or Earthquake (and to a lesser extent, Rock attacks) is preferable, since they would be the favoured attacks on Registeel.
- Pressure stalling Registeel's offensive moves is another strategy, which, despite being boring and lengthily, is effective. Unfortunately, that doesn't stop Registeel from doing the same thing to you.

The basic strategy is to not let Registeel get away with using Curse. Haze, Taunt, Whirlwind and Roar are the core moves you'll need to use. Will-o-Wisp helps nullify Registeel's offence until it's forced to Rest.
- Just like all Pokémon, Perish Song Traps and surprise Destiny Bonds will KO Registeel, so I guess it deserves a mention.

Catching Registeel:

Since Registeel is one of the RSE trio-legends, I figured I'd mention how to catch Registeel.

Firstly, to locate Registeel, follow these guides.

Ruby or Sapphire
Emerald

Once you've unlocked Registeel's location, save in front of it.

Now onto catching it:

Firstly, it is VERY difficult to catch due to its legendary status. Ultra-Balls are the best way to go, although it is possible to catch it in lesser-Pokéballs.
- The continuous Pokéball throwing is a usable strategy, however it is entirely luck-based and it'll take many restarts before you can catch it.

With most Pokémon, lowering its stats make it easier to catch. With Registeel, this can't be done due to clear body. However, if you use Skill Swap (and give it a bad new trait) it allows you to use stat lowering manoeuvres. Lower it's defensive stats a bit and it'll give a 2-fold bonus. Firstly, it'll make it easier to catch and secondly, it'll make it easier to weaken.

Give it a status, preferably Paralysis or Sleep (since Poison or Burn could end up knocking it out).

Finally, weaken it as close possible to 1 HP. There are two strategies to get it down to 1HP:
- If you can get a Pokémon of your own down to 1 HP and use Endeavour, then you have problem solved. The best way to do this is to get the Pokémon poisoned and walk around a little bit. Cure the poison just before it faints and then switch into first place (since it's risky to switch it in).
- False Swipe is the other way. This works best after using Screech multiple times and after weakening Registeel, since a not very effective Base 40 Attack isn't about to bring Registeel down to 1 HP with one hit.

If you have no access to either of these two moves, just make sure you get Registeel into the lower red zone (it takes a couple of hits to do so).

One very important thing to remember is not to let Registeel get away with using Curse. After a few Curses it becomes near impossible to catch due to having beefed up stats (the higher the stats, the harder it is to catch the Pokémon). Taunt and Haze become important to prevent Registeel from getting away with said boosts.

When you find Registeel it'll be Level 40 with the following moves:

Metal Claw
Curse
Super Power
Ancient Power

Contest Moveset

A good Contest Moveset for Registeel would have to be this for the Beauty Contest best with Modest, Mild, Rash or Quiet Nature:

Attacks:

Sunny Day
Explosion
Thunderwave
Aerial ace

Items Attached:

Blue Scarf

Strategy Using Registeel

If you do the attacks in this following order you should have very few problems; 1st - Aerial ace, 2nd - Thunderwave, 3rd - Aerial ace, 4th - Sunny day, 5th - Explosion

Locations in Games

Ruby/Sapphire/Emerald Ancient Tomb on Route 120 Colosseum Trade from R/S/E Fire Red/Leaf Green Trade from R/S/E

Animé Appearences

Registeel has yet to have an appearence in the Pokémon Animé or Movies