Steven is the last challenge in the Ever Grande City gauntlet, but only in Ruby and Sapphire.
Steven's RS battle sprite.
His team in those games is as follows: Level 57 Skarmory (Steel Wing/Toxic/Aerial Ace/Spikes), Level 55 Claydol (Earthquake/Ancientpower/Light Screen/Reflect), Level 56 Aggron (Earthquake/Dragon Claw/Thunder/Solarbeam), Level 56 Cradily (Ancientpower/Confuse Ray/Sludge Bomb/Giga Drain), Level 56 Armaldo (Ancientpower/Slash/Aerial Ace/Water Pulse), Level 58 Metagross (Meteor Mash/Earthquake/Psychic/Hyper Beam). Your reward for beating him is entry into the Hall of Fame and 11,600 Poke Dollars.
Tips for Beating Steven[]
Bring wide coverage: Despite Steven (nominally) being a Steel type specialist, he does a very good job
Steven's room in Ruby and Sapphire.
of not stacking up weaknesses to a specific type of moves. You'll have to use everything you know about the type chart to hit his weak points. Here are some less obvious matchups that might make your life easier:
Electric moves do neutral damage to Steel types. This gives you another way to hit Skarmory super effectively (and with a special type, no less), as well as hitting Metagross neutrally.
Both Cradily and Armaldo are weak to Steel. If you find yourself needing an extra coverage move for either of those two, you might consider something like Steel Wing or Iron Tail. There are a number of Pokemon that can make good use of those moves.
Water also does neutral damage to Steel types, and has the added bonus of being super effective against Claydol and Armaldo. Further, Water resists Steel, granting you a way to stand up to Metagross's fearsome Meteor Mash.
Get quick KOs against Skarmory and Claydol: Steven's Skarmory and Claydol both carry setup moves that will make your life much harder if they're allowed to use them. Skarmory can set up Spikes, which damage every grounded Pokemon you switch in for the duration of the fight (unless you bring Rapid Spin, which is laughably weak and generally not worth the moveslot); Claydol has both Reflect and Light Screen, which reduce the damage you do to Steven's Pokemon for five turns per use. It is important that you not allow Steven's team to use these moves if at all possible, so bring your best sweepers and/or wallbreakers for those matchups.
Don't rely too much on defense: It's extremely hard to find a Pokemon that can completely wall Steven's dedicated attackers, particularly Metagross. Therefore, you should maintain an aggressive, KO-centered mindset in this fight. If you try to play defensively, you're leaving yourself open to an inopportune critical hit or a coverage move. It's also better to try and break through his walls quickly, thanks to their dual-screens and confusion shenanigans (Claydol and Cradily respectively).
Good Pokemon to Use[]
Water types: Their STAB moves are exceptionally useful in this fight, and they also resist a couple key moves on Steven's team. Special mention goes to Swampert, whose additional Ground STAB is super effective against Metagross and Aggron; and Lanturn, whose additional Electric STAB is useful for dispatching Skarmory. Sharpedo is another good option with Surf and Crunch attacks. In Emerald, you can use Octillery and Surf instead.
Fighting types: A good option is Heracross with Brick Break or Megahorn against Cradily, and also inflict great damage against Aggron.
Magneton: While half of Steven's team does carry Earthquake, Magneton does have some notable uses in this fight. Its Electric STAB is very handy against Skarmory and it can also strike heavy blows against Armaldo. While Water Pulse does target Magneton's weaker Special Defense with neutral coverage, bear in mind that Armaldo is an unimpressive user of special moves. Lastly, while it does technically resist all of Cradily's attacking moves, it can't do much in return outside of Toxic stall, which is less than ideal.
Powerful Pokemon with wide movepools: This is a very broad category, but the alternative was making the bullet point label about a line and a half long. Anyways, you want wallbreakers and sweepers with a lot of coverage options so you can get those desirable quick KOs and minimize the turns you spend switching around to Pokemon best suited for each opponent. Exploud springs to mind as an example of a wallbreaker in this category, and Starmie is always an excellent example of a sweeper.
Fire types: Camerupt can use Flamethrower (buy in Mauville Game Corner) against Skarmory and Metagross. In Emerald, you can use Houndoom and Flamethrower instead.
