Hello, everyone. I made this guide for myself, but DarkestLight has suggested that it would be fun to have it posted here, so here it is. The purpose of this guide is to help train your Pokemon on Black/White after you have defeated the Elite 4 at least once. here I will list the places where you can find re-matchable trainers, their Pokemon and the EVs they give out.
I am not including The Riches in Undella Town because they're only re-matchable for 6 days, after which they admit their defeat and stop challenging you. Some trainers can only be challenged at certain times, which will be detailed below.
You may also get some items out of this. And money too. I will not list them here, however, because this guide focuses on training. Everything else you can get while doing this is a bonus.
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Big Stadium and Small Court (Nimbasa City, once a day at almost any time)
Everyday you can enter the Big Stadium and Small Court for a few matches against both athletes and spectators. Sometimes there will be a match going on and you'll have to wait for an hour or two before you can enter, but don't worry: once the match is over, all the trainers you have not yet challenged will be waiting for you to battle them. The set of trainers changes at midnight.
Each day, at each one of these domes, you can battle 3 athletes, 3 spectators and two pairs of backers. The backers will challenge you to a 2-on-2 battle. Some of the spectators will give you an item after you defeat them. Spectators change randomly every day, while the set of athletes and backers is fixed for each sport. I will least all the spectators I have found (and edit this post if I find any new ones), and then the athletes and backers you can battle during each practice.
Levels range between 60 and 68, and their stats are not too bad but not too high either. Athletes are listed by order of proximity to the entrance (from closest to furthest).
Spectators:
-Ace Trainer (female): Jynx (2 Special Attack), Vaporeon (2 HP), Gliscor (2 Defense).
-Ace Trainer (male): Galvantula (2 Speed), Tropius (2 HP), Mamoswine (3 Attack).
-Artist: Smeargle (2 Speed).
-Backpacker (female): Flareon (2 Attack).
-Backpacker (male): Zangoose (2 Attack).
-Baker: Torkoal (2 Defense), Miltank (2 Defense).
-Battle Girl: Hitmonchan (2 Special Defense).
-Black Belt: Mankey (1 Attack), Conkeldurr (3 Attack), Heracross (2 Attack).
-Breeder (female): Swinub (1 Attack), Larvitar (1 Attack), Poliwag (1 Speed), Gible (1 Attack), Cleffa (1 Special Defense), Igglybuff (1 HP).
-Breeder (male): Bonsly with Sturdy (1 Defense), Wooper (1 HP), Munchlax (1 HP), Spoink (1 Special Defense), Wynaut (1 HP), Sandshrew (1 Defense).
-Clerk (female, read her speech and talk to her after the battle): Cherubi (Special Attack), Cherrim (2 Special Attack), Sunflora (2 Special Attack).
-Clerk (male) #1: Yanmega (2 Attack), Ledian (2 Special Defense), Scolipede (3 Speed), Kricketune (2 Attack), Scizor (2 Attack).
-Clerk (male) #2 (older): Persian (2 Speed), Honchkrow (2 Attack).
-Dancer: Mr. Mime (2 Special Defense), Mr. Mime (2 Special Defense).
-Depot Agent: Diglett (1 Speed), Dugtrio (2 Speed).
-Doctor: Audino (2 HP).
-Fisherman: Finneon (1 Speed), Gorebyss (2 Special Attack), Lumineon (2 Speed), Huntail (1 Attack, 1 Defense).
-Gentleman: Slowking (3 Special Defense).
-Harlequin: Exeggcute (1 Defense), Electrode (2 Speed).
-Hiker: Geodude with Sturdy (1 Defense), Graveler (2 Defense), Golem (3 Defense). All explosive.
-Janitor: Koffing (1 Defense), Weezing (2 Defense).
-Lady: Illumise (1 Speed).
-Lass: Misdreavus (1 Special Defense), Pachirisu (1 Speed), Delcatty (1 HP, 1 Speed).
-Maid: Growlithe with Intimidate (1 Attack), Cinccino (2 Speed).
-Musician: Chatot (1 Attack), Wigglytuff (3 HP).
-Nurse: Audino (2 HP).
-Nursery Aide: Clefairy (2 HP), Clefable (3 HP).
-Parasol Lady: Castform (1 HP).
-Pilot: Hoothoot (1 HP), Swellow (2 Speed), Unfezant (3 Attack).
-Pokefan (female): Rattata (1 Speed), Bidoof (1 HP), Sentret (1 Attack), Patrat (1 Attack), Zigzagoon (1 Speed).
-Pokefan (male): Slowpoke (1 HP), Slowbro (2 Defense).
-Policeman: Arcanine with Intimidate (2 Attack), Mienshao (2 Attack).
-Preschooler (female): Smoochum (1 Special Attack).
-Preschooler (male): Mime jr. (1 Special Defense).
-Psychic (female): Mismagius (1 Special Attack, 1 Special Defense), Gothitelle (3 Special Defense).
-Psychic (male): Girafarig (2 Special Attack), Sigilyph (2 Special Attack), Claydol (2 Special Defense).
-Ranger (female): Musharna (2 HP), Drifblim (2 HP), Umbreon (2 Special Defense).
-Ranger (male): Ambipom (2 Speed), Carnivine (2 Attack), Steelix with Sturdy (2 Defense).
-Rich Boy: Volbeat (1 Speed).
-Roughneck: Mightyena with Intimidate (2 Attack), Skuntank (2 HP), Crawdaunt (2 Attack).
-School Kid (female): Dunsparce (1 HP), Luvdisc (1 Speed), Delibird (1 Speed).
-School Kid (male): Seadra (1 Defense, 1 Special Attack), Pupitar (2 Attack), Dragonair (2 Attack).
-Scientist (female): Skorupi (1 Defense), Swalot (2 HP).
-Scientist (male): Stunky (1 Speed), Muk (1 HP, 1 Attack).
-Socialite: Sableye (1 Attack, 1 Defense), Liepard (2 Speed).
-Veteran Trainer (female): Relicanth (1 HP, 1 Defense), Magcargo (2 Defense), Glaceon (2 Special Attack), Dragonite (3 Attack).
-Veteran Trainer (male): Jolteon (2 Speed), Skarmory with Sturdy (2 Defense), Sandslash (2 Defense), Tyranitar (2 Defense).
-Waiter: Clamperl (1 Defense), Glameow (1 Speed), Unfezant (3 Attack).
-Waitress: Psyduck (Special Attack), Leafeon (2 Defense).
-Worker (Cold Storage): Sealeo (2 HP), Glalie (2 HP).
-Worker (Road): Mawile (1 Attack, 1 Defense), Excadrill (2 Attack).
-Youngster: Venonat (1 Special Defense), Venomoth (1 Speed, 1 Special Attack), Raticate (2 Speed).
Baseball practice (Big Stadium)
Infielder #1: Simipour (2 Speed), Simisage (2 Speed), Simisear (2 Speed).
Infielder #2: Unfezant (3 Attack), Krookodile with Intimidate (3 Attack).
Infielder #3: Cubone (Defense), Bisharp (2 Attack).
Female Backers: Simipour (2 Speed), Simisear (2 Speed).
Male Backers: Simisage (2 Speed), Bisharp (2 Attack).
Soccer practice (Big Stadium)
Striker #1: Taillow (1 Speed), Sneasel (1 Speed), Liepard (2 Speed).
Striker #2: Swanna (2 Speed), Kecleon with Synchronoise (1 Special Defense).
Striker #3: Lunatone (2 Special Attack), Solrock (2 Attack).
Female Backers: Swanna (2 Speed), Swanna (2 Speed).
Male Backers: Liepard (2 Speed), Liepard (2 Speed).
American Football practice (Big Stadium)
Backer #1: Lickitung (2 HP), Conkeldurr (3 Attack), Darmanitan (2 Attack).
Backer #2: Sawk with Sturdy (2 Attack), Throh (2 HP), Hariyama (2 HP).
Backer #3: Forretress with Sturdy (2 Defense).
Female Backers: Sawk with Sturdy (2 Attack), Throh with Wide Guard (2 HP).
Male Backers: Darmanitan (2 Attack), Darmanitan (2 Attack).
Basketball practice (Small Court)
Hoopster #1: Mantyke (1 Special Defense), Scolipede (3 Speed).
Hoopster #2: Stoutland (3 Attack), Gigalith with Sturdy (3 Attack).
Hoopster #3: Masquerain with Intimidate (1 Special Attack, 1 Special Defense), Bouffalant (2 Attack).
Female Backers: Stoutland with Intimidate (3 Attack), Bouffalant (2 Attack).
Male Backers: Scolipede (3 Speed), Gigalith with Sturdy (3 Attack). This Gigalith will use Sandstorm even though it hurts Scolipede.
Tennis practice (Small Court)
Smasher #1: Baltoy (1 Special Defense), Zebstrika (2 Speed).
Smasher #2: Whimsicott (2 Speed), Lilligant (2 Special Attack).
Smasher #3: Voltorb (1 Speed), Jellicent (2 Special Defense).
Female Backers: Whimsicott (2 Speed), Lilligant (2 Special Attack). This Whimsicott is mostly harmless, bring down Lilligant first.
Male Backers: Zebstrika (2 Speed), Jellicent (2 Special Defense).
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GameFreak Morimoto (Castelia City, GameFreak building 22F, once a day at any time)
Morimoto's Pokemon are level 75-77, but their stats are low, so they're easy to beat if you have trained Pokemon above level 65. All his Pokemon give out Speed EVs (2 EVs each).
His Pokemon are: Liepard, Simipour, Simisear, Simisage, Zebstrika, Swoobat.
Note: his Liepard always begins with Fake Out. I suggest starting either with a Pokemon who can't flinch or one with the Intimidate ability (then you can switch to whatever Pokemon you want, you'll lose the turn anyway but at least you've lowered Liepard's Attack).
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Royal Unova (Castelia City, first dock, everyday at 5 PM on most seasons, 7 PM in the summer)
Here you can find from 3 to 7 opponents depending on the day. Talk to the crew and keep track of the following data:
1.- How many trainers are behind the blue doors.
2.- How many trainers are on each side of the ship.
3.- How many trainers you have found behind blue doors and how many behind brown doors.
4.- What trainers you have already battled.
That should give you enough information to defeat all trainers on most days. I recommend starting by checking the doors on the side that has the most trainers, so that once you've faced all the trainers on that side your choices for the other side are pretty narrow (you don't get to challenge the same trainer twice, and you'll know what colors their doors will have). These are the trainers you can find. Their Pokemon's levels range between 63 and 66.
-Youngster (a.k.a. boy in shorts): Spearow (1 Speed), Fearow (2 Speed), Linoone (2 Speed).
-Rich Boy: Aipom (1 Speed), Murkrow (1 Speed).
-Clerk (male): Ariados (2 Attack), Floatzel (2 Speed).
-Ace Trainer (male): Tauros (1 Attack, 1 Speed), Wailord (2 HP).
-Ace Trainer (female): Rotom (1 Speed, 1 Special Attack), Butterfree (1 Special Attack, 1 Special Defense), Alomomola (2 HP).
-Lass: Chingling (1 Special Attack), Wormadam (2 Special Defense).
-Lady: Meowth (1 Speed), Eevee (1 Special Defense), Vulpix (1 Speed).
-Maid: Emolga (2 Speed).
-Gentleman: Houndour (1 Special Attack), Houndoom (2 Special Attack), Noctowl (2 HP).
-Socialite: Liepard (2 Speed), Arbok (2 Attack).
Don't talk to Pokefans, they're never trainers.
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Cynthia (Undella Town, once a day in the Spring and Summer)
Cynthia's Pokemon are level 75-77 with high stats, good moves and few to no weaknesses, and on top of that she uses Full Restore, so watch out if your Pokemon's levels are lower than hers. She's tougher than any other trainer in the game, including Alder.
Cynthia's Pokemon: Spiritomb who uses Double Team like crazy and also Will-o-Wisp (1 Defense, 1 Special Defense), Milotic with a mean Blizzard (2 Special Defense), Eelektross (3 Attack), Braviary (2 Attack), Lucario (1 Attack, 1 Special Attack), Garchomp (3 Attack).
Note: a Pokemon with Flash Fire works best against Spiritomb, especially if it also knows Will-o-Wisp or Toxic. Cynthia will use Full Restore on her, but only once. Against Milotic, a Grass Type with Sleep Powder and a Yache Berry did the trick for me when I faced her at level 65. The others were tough, but not so terrible.
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Bianca (Prof. Juniper's lab, Numeva Town, once every Saturday and Sunday)
Bianca's Pokemon are level 63-65, with good stats. You can rematch her on weekends after you've defeated Alder at least once. Her starter and Simi depend on which starter you chose. Her other Pokemon are the following:
Stoutland with Intimidate (3 Attack), Musharna (2 HP), Mienshao (2 Attack), Chandelure (3 Special Attack).
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Cheren (Victory Road, right door coming down from the Pokemon League)
Here I'm assuming you've already talked to Cheren after your first confrontation with the Elite 4. Otherwise, go to Route 5 and talk to him first, then you'll be able to find him on Victory Road and battle him once a day. His Pokemon are level 65-67 and slightly stronger than Bianca's. His starter and Simi depend on your choice of starter. The others are:
Liepard with Fake Out (2 Speed), Gigalith with Sturdy (3 Attack), Unfezant (3 Attack), Haxorus (3 Attack).
Note: his starter has a Focus Sash.
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Musharna (Dreamyard basement, Fridays only)
OK, this is not a trainer and it's not even a rematchable Pokemon since it's a different Musharna each time, but if you go to the Dreamyard basement on a Friday you can battle a level 50 Musharna. Or you can catch it if you want, either way a new one will show up the following week. Friday Musharna's gender and stats vary, but their ability is always Telepathy.
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Ace Trainer Glinda (Marvelous Bridge, East exit, only once every time you defeat the trainer at the Ground Floor of the Battle House)
Glinda will challenge you to a triple battle in Black or a rotation battle in White. Her Pokemon are level 65 with good stats and good teamwork, but if you've defeated Alder, she should be no problem for you.
Her Pokemon are: Beheeyem (2 Special Attack), Klinklang (3 Defense), Alomomola with Wide Guard (2 HP).
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Options for lower-level Pokemon:
Ferris Wheel trainers (Nimbasa City Amusement Park)
These trainers will invite you to battle them and ride the Ferris Wheel with them, and some of them may flirt with you while they're at it. Their Pokemon are level 24-27, and they change with the seasons. Male and female players get different opponents.
Season For female trainers For male trainers Spring Dancer Dirk: Darumaka (1 Attack) Hiker Andy: Boldore (1 Attack, 1 Defense) Summer Ace Trainer Austin: Swoobat (2 Speed) Clerk Trisha: Minccino (1 Speed) Autumn Waitress Aurora: Swadloon (2 defense) Lass Maya: Gothita (1 Special Defense) Winter Rich Boy Martin: Tranquill (2 Attack) Preschooler Winter: Solosis (1 Special Attack)
Battle House (Opelucid City)
Here you can have Rotation Battles against level 39 Pokemon. The ground floor is good for Speed EV-training. I do not recommend the top floor for this because it gives out both Attack and Special Attack EVs, and little experience; but if you have 3 Pokemon who use both Physical and Special attacks, go ahead.
Ground floor: Simisage (2 Speed), Simipour (2 Speed), Simisear (2 Speed).
Top Floor: Mienfoo (1 Attack), Elgyem (1 Special Attack), Pawniard (1 Attack).
Bikers Gang (Tubeline Bridge, Fridays, same times as the Royal Unova)
Their Pokemon are levels 35-37. As soon as you enter the bridge, a biker will challenge you. Answer 'No' to his question and battle him. Then search for the leader (usually found riding slowly by the lower-right side of the bridge) and battle him too. Then they'll name their gang after the first Pokemon in your party, even if tat was already their name (they're not that smart). Next time you face them, they'll have forgotten you but they'll still be named after your Pokemon.
Biker Morgann: Bouffalant (2 Attack)
Biker Jeremy (leader): Joltik (1 Speed), Krokorok (2 Attack), Scraggy (1 Attack).
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And, of course, you can always rematch the Elite 4 if you're willing to go to the whole process again. And if you're lucky enough to have trainers in your Black City or White Forest, you can rematch them everyday.