As with almost every Pokémon game, beating the Elite Four and the Champion isn't the end of your Pokémon League challenge. In addition to unlocking a bunch of new content elsewhere in Unova, trouncing the League also triggers a significant boost to the Elite Four in the Champion. All of their Pokémon get significantly stronger, and every member of the Elite Four receives new Pokémon to bedevil your own team. Care for a rematch?
Aside from money, experience, and some new dialogue, beating Iris - and the Elite Four, for that matter - doesn't earn you anything new the second, third, fifth, or twentieth time around. These five trainers are nevertheless one of the best ways to level up your Pokémon, so feel free to keep challenging the Pokémon League until you're sick of the place.
Elite Four Shauntal (Bottom Left)
- Cofagrigus, level 72
- Mismagius, level 72
- Frosslass, level 72
- Drifblim, level 72
- Golurk, level 72
- Chandelure, level 74
Reward: 8,880 P
The battle against Shauntal doesn't change a whole lot. Cofagrigus is still the irritating starter who burns your team, Chandelure is the swift sweeper you need to outpace, and the rest are of middling potency. Shauntal gains Frosslass and Mismagius for this fight, and both are speedy but frail, similar to Chandelure. Mismagius always starts with Perish Song, knocking out it and your active Pokémon within three turns, so be ready to send out someone else after that first turn. If you go into this match with a strong Dark-type you shouldn't have much trouble sweeping Shauntal's team.
Elite Four Marshal (Bottom Right)
- Throh, level 72
- Sawk, level 72
- Lucario, level 72
- Mienshao, level 72
- Medicham, level 72
- Conkeldurr, level 74
Reward: 8,880 P
Marshal has added some variety to his team, and where he only had Fighting-types previously he's now mixed things up a bit by throwing in Steel-type Lucario and Psychic-type Medicham. Both will resist Psychic-type moves, so if you've been using Psychic to plow through Marshal's team up to this point you may have some trouble. Fighting-, Ground-, and Fire-type moves are all good against Lucario, while Flying- and Ghost-type moves work well on Medicham. (Be careful deploying a Flying-type against Medicham, though, as it knows Ice Punch and ThunderPunch.) The rest of Marshal's team remains bulky, but vulnerable to Special Attack moves.
Elite Four Grimsley (Top Left)
- Liepard, level 72
- Honchkrow, level 72
- Scrafty, level 72
- Krookodile, level 72
- Houndoom, level 72
- Bisharp, level 74
Reward: 8,880 P
Grimsley's team remains, by and large, fast, strong, and a bit frail. The Dark-type master adds Honchkrow and Houndoom, and while Houndoom is pretty straightforward Honchkrow puts a stopper on the types that usually sweep this gym. It can be especially dangerous to Fighting-types because it knows Psychic, which can prove a nasty surprise if your Pokémon is on the slower side. It also knows Aerial Ace, which will trounce any Bug-types you might deploy. Rock-type moves can wipe out both Honchkrow and Houndoom with minimum effort. Get past Honchkrow and the rest of Grimsley's party remains quite vulnerable to Fighting-type moves, and to a lesser extent Bug-type moves.
Elite Four Caitlin (Top Right)
- Musharna, level 72
- Sigilyph, level 72
- Reuniclus, level 72
- Gothitelle, level 72
- Gallade, level 72
- Metagross, level 74
Reward: 8,880 P
Caitlin remains a well-balanced trainer, adding an offensive powerhouse and a defensive powerhouse to her lineup. Her new Pokémon are Gallade and Metagross, both of which are quite effective at singling out and eliminating the obvious Dark-types that you might deploy to deal with Caitlin's team. Gallade hits very hard in general, and Metagross is difficult to defeat in a single turn unless your attacker is vastly overleveled. Ghost-type moves can deal with both, though if you have a fast Flying-type you may want to use a physical Flying-type move to wipe out Gallade instead, as its Defense is poor. Avoid physical moves on Metagross, as they'll almost never give you a quick win.
Champion Iris
- Hydreigon, level 76
- Druddigon, level 76
- Aggron, level 76
- Archeops, level 76
- Lapras, level 76
- Haxorus, level 78
Reward: 11,800 P
Iris is an odd duck as far as rematches go in that, if you look past the raw levels, she's a bit easier to beat the second time. Her Pokémon have all had their moves shuffled around, and while they've been replaced with stronger alternatives many of their new attack options are less accurate. The chances of your Pokémon getting OHKOed are higher, but the chances of her Pokémon just outright whiffing their attacks are also pretty decent.
You should nevertheless stick to the same strategy you used previously, playing to each of Iris' weaknesses based on your team composition. Ice-type moves remain a great option against four of her six Pokémon, while Fighting-type moves are a great option for Aggron and Lapras. (And Hydreigon, for that matter.) The battle is still a bit of a slog, but if you've poked around post-game Unova and picked up levels and new TMs beating Iris shouldn't be a massive challenge.