By far the most well-known Self-Imposed Challenge in the Pokémon series is the "Nuzlocke Challenge". Nuzlocke runs are a variant of the Permadeath run, with the name for the ruleset coming from Nuzlocke Comics. The basic rules of the format are that any Pokémon that faints is considered dead and can't be used for the rest of the run, you can only catch the first wild Pokémon encountered in each area — if they faint or flee, tough lucknote Plot-mandated captures are exceptions, but actually using them depends on your preference — and the player must nickname all of their Pokémon, so they can be more emotionally attached to them. That last one isn't actually part of the original ruleset, but enough people adhere to it that it can be odd to see someone not do it for their runs. Speaking of, there are also an assortment of additions made to the ruleset for the sake of both convivence and challenge, such as the "Species/Dupes clause" (you can try again if the first encounter in an area is a Mon you already have). Later generations also have self-imposed Obvious Rule Patches to prevent taking advantage of mechanics that would trivialize the challenge, like not being allowed to use the DexNav in Pokémon Omega Ruby and Alpha Sapphire or avoiding visible overworld encounters in Pokémon Sword and Shield.
The "Wonderlocke Challenge" is a variant seen in Gen VI games and beyond, wherein any Pokémon caught must immediately be traded through Wonder/Surprise Trade, and the received Pokémon is to be used instead. This sometimes comes with a level restriction where, if the received Pokémon is too strong relative to that area of the game (e.g., getting a level 40 Mon when you haven't even beaten the first Gym yet), you must continue to trade until you get an appropriately leveled Pokémon.
Marriland's "Wedlocke Challenge", which requires you to pair up your Pokémon into Battle Couples. In battle, you can only swap out a Pokémon for its partner, and a pair is permanent until one of the Pokémon dies; in which case, the partner must try to "avenge" their loved one and finish the battle before they can be reassigned a new one.
Other Challenge Runs and Self-Imposed Rules
In general, the most common self-imposed rules that you'll find used, either on their own or in conjunction with the various challenges listed on this page, include no item use during battle (this may or may not include held items), using "set" battle mode, and banning the use of Legendary and Mythical Pokémon. Refusing to use Legendaries and Mythicals during the main game is actually a common enough occurrence that even casual players tend to abide by this rule.
Solo Character Runs, with the challenge of these runs being highly dependent on what Pokémon you choose. While there are definitely plenty of Pokémon that make such an attempt difficult, if not impossible (especially if you throw in a "No Evolution" clause), there are also a fair number that can actually make a Solo Pokémon Run easier than a normal one. An over-leveled Pokémon with good stats and a sufficiently versatile moveset can brute force their way through pretty much anything, as it's easy for most Mons to shrug off type disadvantages when they're thirty levels higher than the opponent, and your starter is definitely a member of this group.note In fact, it isn't uncommon for younger first-time players to use only their starter in battles throughout most of the game because of this. The idea of training the rest of the team never comes to mind because their awesome pet dragon or otter is handling everything by itself. All you'll need are a few PP-restoring items for the Elite Four and (in earlier generations) an extra Pokémon or two whose only purpose would be to hold mandatory HM moves, if your chosen Pokémon can't learn all the required ones. On the other hand, use a Pokémon that doesn't have a good moveset or base stats (like a first-stage Bug-type), or an odd gimmick (like Ditto or Shedinja), and you will find yourself forced to come up with some interesting strategies to get to the end credits.
Mono-Type has you act as an unofficial Gym Leader, as you're only able to use Pokémon of a single type. Depending on the game, this can greatly limit your team selection; for example, attempting a Mono-Fire run in Diamond & Pearl leaves you with only the fire starter and the Ponyta evolutionary lines to work with.
No-Evolution. As the name suggests, you aren't allowed to evolve your Pokémon. Pokémon that don't evolve whatsoever are fair game. Some players will allow themselves to catch mid-stage Mons if they appear in the wild, while others also allow final stage evolutions found in the wild.
Permadeath runs: if a Pokémon faints, you must release it. Good luck with the Elite Four. In a similar vein, the "No-Whiteout" challenge forces you to restart the game from the beginning if all your Pokémon faint. If you're really hardcore, you can make a No-Damage Run, which is nigh impossible — but it's been done before. Gamerchamp3000 tried this in their VG Myths series and beat Pokémon Bluewithout taking a single hit, with one of the rules being that Save Scumming wasn't allowed and that they'd have to start from the very beginning if they took damage. Another player, Smallant1 also pulled it off in Platinum, though with a rule that he could save after defeating every gym, with those serving as checkpoints.
"Shiny Only" runs. Runs where only shiny Pokémon can be used, usually requiring loads and loads of Save Scumming gifted Pokémon (starters or Eevees typically) or guaranteed encounters (legendary encounters usually) until a shiny is found. The most popular is G/S/C/HG/SS, as a shiny Gyarados is a guaranteed encounter.
The "Living Pokédex" Challenge for completionists and collectors. This challenge takes Gotta Catch Them All to its logical extreme, as you're required to have one of every species in that game's National Pokédex at once in your PC. Bonus points if you organize them in proper order. True Pokémaniacs can take even that Up to Eleven with the "Living Shinydex" challenge, which is the same but with the ultra-rare Shiny Pokémon — including the one-time-only Legendaries. Have fun spending literal days soft-resetting the game 1,000+ times until you get that Shiny starter Pokémon! note And Arceus help you if your game is one that requires you to go through a long cutscene between the closest save point and actually getting that starter, like Pokémon X and Y or Pokémon Sun and Moon. Doubly so if Damn You, Muscle Memory! decides to screw you over and you automatically soft-reset before your brain registers that, yes, that was a shiny.
"Professor Oak's Challenge" requires you to catch and evolve as many Pokémon as possible before each Gym badge, completing as much of the regional Pokédex as you can with the minimum amount of badges possible. You must do this in a single playthrough and using only one copy of the game, meaning trade evolutions and version exclusives aren't available.
NPC runs, where you roleplay as an A.I. trainer, be they Bug Catchers, evil team Grunts, or Gym Leaders. This means you have to use the same species of Pokémon they have (evolution may or may not be allowed), and you aren't allowed to use healing items in battle.note If you're roleplaying a trainer that does, such as a Gym Leader, you're limited to the same amount as them. This may also limit the number of Pokémon you can have on your team.
The "Team Rocket Challenge" is a related challenge.
- You must have a cheating device with a "catch Trainer Pokémon" cheat available at all times. note Wait, are we talking about Team Rocket or Cipher? - The only "wild" Pokémon you may use (outside of your starter) are of Bug, Dark, Ghost, and Poison type, and the Rattata line or that generation's equivalent (Sentret, Zigzagoon, Bidoof, Patrat). - You may use Pokémon outside the above types only by stealing them from fellow Trainers. - When battling an important Trainer (Rival, Gym Leaders, Team Leaders, Elite Four, Champion), you may only steal their last Pokémon. - If the game you are playing has Team Rocket as the enemy team, avoid as many Team Rocket battles as possible. If the enemy team is not Team Rocket, you must battle them as much as possible.
The "Gary Oak Challenge", which attempts to mirror your Gen I rival's game progression, and is really grind-heavy as a result. How he did all this and still managed to beat you to the Elite Four is beyond us:
- You must capture every unique Pokémon you can on the first available route. - Once you have more than six Pokémon, you must constantly rotate team members so that every Pokémon is used regularly in battle. - All Pokémon must be leveled up evenly, and they cannot be at a higher level than the Rival's strongest Pokémon at that point in the game. - Pokémon who evolve by means other than leveling up must be evolved as soon as possible.
The "Scramble" challenge: another player picks your team for you. That's your definitive team throughout the game; you can't evolve them. (Sucks if you're stuck with Magikarp and Wurmple.) A variant has you do this with eggs, as no one knows what's inside them until they hatch. The "Wonder Trade Challenge", only possible from Pokémon X and Y onward, is a variant where all Pokémon you catch must be Wonder Traded, and you're stuck with whatever you get in return. If you get a duplicate, Wonder Trade it again. Some variants require that instead of releasing fainted Pokémon, you must Wonder Trade them again.
The "N Challenge" originated in Pokémon Black and White, but can be done in other entries. You're not allowed to nickname your Pokémon and all of them are temporary party members; you must designate a certain point (e.g. after every Gym battle or rival fight) where you dump your team and catch new Pokémon, although you're allowed to keep one Pokémon after the fifth gym (and some variants allow you to keep your starter as well). Your team against the Elite Four must also contain at least one legendary (a real one — pseudo-legendaries don't count).
- No evolving your Pokémon. - No Dark, Psychic, or Ghost Pokémon or moves. - No Ekans, Arbok, Seviper, or Serperior. - Pokémon must be Level 22 before they can breed. - Pokémon of the same gender cannot share a daycare center. - It is your duty to keep any egg Pokémon in the party until Level 18. - Legendaries are false idols and should be killed. - No Fossils, Game Corners, or drugs (PP Up, Rare Candy, etc.).
- Avoid battles wherever possible. - Never make wild Pokémon faint. - Don't catch more than you can carry (i.e. don't use PC boxes). - You must pick up items on the ground. - Never throw out items. - Don't buy supplies from Poké-Marts if you can help it.
- Choose one Nation to be a part of, be it Waternote Water, Ice, Grass, and Poison, Earthnote Ground, Rock, Steel, and Fighting, Firenote Fire, Electric, Dark and Dragon, or Airnote Flying, Psychic, Ghost, and Bug. Only catch Pokémon that are in your respective element. You are not the Avatar and you've got to deal with it. - You may catch a Pokémon if it can evolve into a type from your nation (e.g. Earth can have a Torchic because it will become a Fighting type). But if it evolves out of your nation, you cannot use it anymore. - Normal and Fairy types are free game (unless they have a secondary type — e.g. anyone can have a Ratatta, but only Air tribes can have a Pidgey).
The "Poké Ball-Only Challenge", which requires you to catch every Pokémon in the Pokédex using only standard Poké Balls. Good luck with the Legendary Pokémon. (You do get a pass for the Safari Zone and the Bug-Catching Contest, which require you to use specific types of balls.)
- You're only allowed to use the Meganium line, the Ampharos line, the Arcanine line, the Espeon line, Lapras and the Dragonite line. (In fact, this team is based on the Pokémon the Tokimeki PokéLive! and TwinBee version of Shizuku uses in that continuity.) - All of them must be female. - All of them must be named after Love Live! characters, though a variant also allows you to name them after characters from similar Idol Genre, Slice of Life and Music franchises like K-On!, Lucky Star, The Idolmaster and Vocaloid for example. - You aren't allowed to breed them for perfect IVs (if you're bringing them over from another game where you bred for them) and you aren't allowed to give them 252 EVs in their Attack stat they specialize in and their Speed stat. - You aren't allowed to cheat, unless you're using a Wild Pokémon Modifier cheat to catch them if you're using an emulator to play. - You must evolve them all the way into their final forms. - You must use them even in the postgame, at least until all of them are level 100. - You aren't allowed to challenge the in-game Battle facilities. - Except for plot-important Legendary Pokémon (Reshiram in Black, Zekrom in White, Xerneas in X and Yveltal in Y.), using Legendaries/Mythicals isn't allowed. - You must play as the female protagonist and name them after Shizuku.
Generations VI and VII had a simple one: Switch off the Exp. Share as soon as you get it. In these two generations, an active Exp. Share gives the full amount of Exp to everyone that battled, and half that to everyone else. Leaving it on makes it stupidly easy to steamroll everyone with a level advantage, but turning it off results in a much steeper difficulty curve. Generation VIII removes the Exp. Share as a toggleable Key Item and instead makes its effects permanent by default, but you can partake in a similar challenge by prohibiting the use of Exp. Candies from the Max Raid battles.
For Pokémon Mystery Dungeon players, their biggest challenges involve Kecleon. Tough players try to recruit Kecleon — but even under the absolute best of conditions, their chance of recruitment is 0.1%. Craftier players try to steal from Kecleon — which will result in swarms of extremely high-level Kecleon attacking you (and they can double the speed of any other Kecleon in the room), and losing will turn the player's entire inventory into totally useless Plain Seeds. Truly gutsy players will try to defeat Kecleon.