The following is a summary of formats and rulesets that are used on the PokeClash server. Some of them are pulled from the core series games developed by The Pokemon Company and Pokemon Showdown by Smogon University. Some events on the server may use exact or modified versions of these formats. Fakemon on the server with strategies for the format will be listed under the corresponding category. Below is a list of common clauses and custom rules sometimes used by events and gym leaders.
| Clause | Description |
| Species Clause | A team may not consist of more than one Pokémon belonging to the same National Dex number. |
| Sleep Clause | You cannot sleep more than one Pokémon on the opposing team. Due to limitations, active sleep moves should not be used once a Pokémon has been slept in case you accidentally sleep another Pokémon. Normally on Pokémon Showdown, sleeping more than one Pokémon is impossible when this clause is active as the system prevents it from occurring. |
| Evasion Clause | You may not use effects that boost evasion. Effects that reduce evasion or alter accuracy are on the table. |
| OHKO Clause | You may not use moves that cause a guaranteed OHKO on the target, like Horn Drill or Sheer Cold. |
| Moody Clause | You may not use the ability Moody. |
| Fakemon Clause | Fakemon may not be used. |
| Modeless Clause | Pokémon that exist only as substitute dolls as they do not have a model or do not spawn in the wild may not be used. |
| PokeShout/OTS | An Open Teamsheet (OTS) must be provided as a screenshot of the team or a PokePaste made via Showdown must be provided prior to battle or a both teams must use the /pokeshoutall command prior to battle. |
| No Stall | A rule with a highly variable definition. Usually entails the ban of Toxic combined with recovery or protection. |
| No Regional Gimmick | Ban on all regional gimmicks, which, includes Mega Evolution, Z-Moves/Crystals, Dynamax/Gigantamax, Terastalization, etc. |
| No Megas | Mega Evolution and its items are not allowed. |
| No Z-Moves/Crystals | Z-Moves/Crystals and its items are not allowed. |
| No Legendary | Legendary Pokémon and their forms are not allowed. This includes: Articuno, Zapdos, Moltres, Mewtwo, Raikou, Entei, Suicune, Lugia, Ho-Oh, Regirock, Regice, Registeel, Latias, Latios, Kyogre, Groudon, Rayquaza, Uxie, Mesprit, Azelf, Dialga, Palkia, Giratina, Heatran, Regigigas, Cresselia, Cobalion, Terrakion, Virizion, Tornadus, Thundurus, Landorus, Reshiram, Zekrom, Kyurem, Xerneas, Yveltal, Zygarde, Type: Null, Silvally, Tapu Koko, Tapu Lele, Tapu Bulu, Tapu Fini, Cosmog, Cosmoem, Solgaleo, Lunala, Necrozma, Zacian, Zamazenta, Eternatus, Kubfu, Urshifu, Regieleki, Regidrago, Calyrex, Glastrier, Spectrier, Enamorus, Wo-Chien, Chien-Pao, Ting-Lu, Chi-Yu, Koraidon, Miraidon, Okidogi, Munkidori, Fezandipiti, Ogerpon, Terapagos |
| No Mythical | Mythical Pokémon and their forms are not allowed. This includes: Mew, Celebi, Jirachi, Deoxys, Manaphy, Phione, Darkrai, Shaymin, Arceus, Victini, Keldeo, Meloetta, Genesect, Diancie, Hoopa, Volcanion, Magearna, Marshadow, Zeraora, Meltan, Melmetal, Zarude, Pecharunt. |
| No Paradox | Paradox Pokemon and their forms are not allowed. This includes: Great Tusk, Scream Tail, Brute Bonnet, Flutter Mane, Slither Wing, Sandy Shocks, Roaring Moon, Walking Wake, Gouging Fire, Raging Bolt, Iron Treads, Iron Bundle, Iron Hands, Iron Jugulis, Iron Moth, Iron Thorns, Iron Valiant, Iron Leaves, Iron Boulder, Iron Crown |
| No Ultra Beast (UB) | Ultra Beasts and their forms are not allowed. This includes: Nihilego, Buzzwole, Pheromosa, Xurkitree, Celesteela, Kartana, Guzzlord, Poipole, Naganadel, Stakataka, Blacephalon |
1v1 is an Independent Unofficial Metagame where players choose a Pokémon that they believe is capable of defeating most—if not all—other Pokémon in a one-on-one situation. Players are allowed to bring a team of three Pokémon to the team preview but must select only one to battle with. So, while your team of three should be able to cover a wide variety of common threats, the Pokémon you send out must be able to beat any of your opponent's Pokémon, or at least the one you think they will use against you.
Battle Stadium Singles (BSS) is the official Singles metagame played on the Nintendo Switch system. This metagame has a static banlist and a different set of clauses than Smogon metagames, though the ruleset changes with each new Regulation. The most notable aspect of this metagame only allows you to select 3 out of your 6 Pokémon to send into battle, and that Pokémon are level 50.
Battle Stadium Singles (BSS) is the official Doubles metagame played on the Nintendo Switch system. This metagame has a static banlist and a different set of clauses than Smogon metagames, though the ruleset changes with each new Regulation. The most notable aspect of this metagame only allows you to select 4 out of your 6 Pokémon to send into battle, and that Pokémon are level 50.
VGC is The Pokémon Company International's official tournament series. This Double Battle format has a fluctuating banlist and a different set of clauses than Smogon metagames. Most notably, it only allows you to select 4 out of your 6 Pokémon to send into battle.
AG (Anything Goes) is a 6v6 singles metagame that has the fewest restrictions found in any of Smogon's formats. Every Pokémon from any tier is allowed, and because the Species Clause is lifted, you can have up to six of the same Pokémon on your team. In fact, all clauses besides Endless Battle are gone, so strategies that are generally deemed uncompetitive such as Moody and Evasion are completely usable here.
National Dex Ubers is a very inclusive tier that allows the usage of as many Pokémon as competitively possible, independently of usage in National Dex OU, National Dex UU, and National Dex RU. As a National Dex format, it uses all of its mechanics.
National Dex is a unique format that strives to make ingame mechanics of the respective generation work with every single Pokémon, including those that have been cut from the Pokédex. This also means that cut moves, Z-Moves, Mega Pokémon, Primal Pokémon, and more are legal.
National Dex UU is the unofficial usage-based format below National Dex OU. As a result, it uses all of National Dex's mechanics.
The following Fakemon are banned from this format:
National Dex RU is the unofficial usage-based format below National Dex UU. As a result, it uses all of National Dex's mechanics.
National Dex is a unique format that strives to make ingame mechanics of the respective generation work with every single Pokémon, including those that have been cut from the Pokédex. This also means that cut moves, Z-Moves, Mega Pokémon, Primal Pokémon, and more are legal.
National Dex Monotype is a variant of Monotype that mixes in the mechanics and validation of National Dex. In the case of a Pokémon that can Mega Evolve, both it and its Mega Evolution must share a type with the rest of the team. For example, Gyarados is a Water / Flying type. It may be used on mono-Water or mono-Flying teams. However, it may only hold Gyaradosite on a mono-Water team. This is because Mega Gyarados is a Water / Dark type, so it would not share a type with a mono-Flying team. By the same principle, regular Gyarados may not be used on a mono-Dark team even if it is holding Gyaradosite.
NFE (Not Fully Evolved) is an Unofficial Metagame in which the main premise is simple: only Pokémon that can evolve are allowed.
LC (Little Cup) is a format where players may only use Pokémon that have not yet evolved, are capable of evolution, and are obtainable at level 5 in-game.