SOS Battles are a brand feature introduced in the Seventh Generation where Wild Pokemon can call for help from other Pokemon. This is seen quite often during Totem Battles in Island Trials, but this can also happen in standard wild encounters as well. As the initial Pokemon gets lower and lower in HP, they will often call for help. This will usually bring another Pokemon into battle, causing it to become a 2-on-1 Handicap Match. While this can be frustrating to some, SOS Battles have a number of benefits to then as the battle carries on.
As the SOS Battle Chain increases, the is a much higher chance of getting Pokemon with Maximum IVs, capping at 4 Max IVs. This is also the only known way in-game of finding Pokemon with their Hidden Abilities. In addition to those perks, the likelihood of encountering a Shiny Pokemon also increases, providing the best odds of finding one in-game.
SOS Battles also help competitively with your Pokemon: as the Chain continues, the Effort Value Points earned from each Pokemon are multiplied by 2 which result in the EVs you receive getting increases. With this concept, plus a Power Item and PokeRus, a Pokemon can get 36 Effort Value Points from just one Pokemon being defeated, which a maxed out stat from 7 KO'd Pokemon in just one Chain.
And SOS Battles can happen in any battle really, but due to these given benefits, players might want to force an SOS Battle, and they can do so in a number of ways. Firstly, a player can keep the initial Pokemon at a low health, allowing it to continue to call for help if it doesn't presently have some. Another way is for players to use the new item called the Adrenaline Orb, which can be used in a Wild Battle for a higher chance of the initial Pokemon calling for help. By also having a Pokemon with the abilities of Intimidate, Pressure or Unnerve, there is a higher chance for a Pokemon getting help. But there is a never a guarantee a Pokemon will call for help; Legendary Pokemon and Island Scan Pokemon will never call for help, Minior and Komala will never call for help, and Status Conditioning doesn't increase the chances either.
But when a Pokemon does call for help, it doesn't always mean the same Pokemon will always come. In all actuality, there are usually eight possible Pokemon per each slot that can be called upon (shown in our Walkthrough Pages). Also, If you knock out the original Pokémon and the new Pokémon isn't part of the same evolution line, then no more Pokémon will be called.
Exclusive SOS Pokemon
Pikachu - Route 1 & Hau'oli City
Clefairy - Mount Hokulani
Jigglypuff - Route 4 & Route 6
Persian - Malie Garden
Slowbro - Kala'e Bay
Gengar - Abandoned Thrifty MegaMart
Seaking - Brooklet Hill & Malie Garden
Starmie - Route 7 & Hano Beach
Mr. Mime - Hau'oli City Shopping District
Jynx - Seaward Cave
Electabuzz - Mount Hokulani
Magmar - Wela Volcano Park
Snorlax - Route 1
Dragonair - Poni Gauntlet & Poni Meadow
Dragonite - Poni Gauntlet
Noctowl - Lush Jungle
Crobat - Lush Jungle & Resolution Cave
Lanturn - Route 8 & Akala Outskirts
Xatu - Akala Outskirts
Sudowoodo - Route 1, Route 5 & Lush Jungle
Slowking - Kala'e Bay
Octillery - Route 8, Kala'e Bay, Melemele Sea
Blissey - Poni Plains
Sableye - Ten Carat Hill & Vast Poni Canyon
Sharpedo - Poni Breaker Coast
Whiscash - Paniola Town, Poni Gauntlet, Poni Meadow, Seaward Cave, Vast Poni Canyon
Cradaunt - Vast Poni Canyon
Huntail - Route 15, Melemele Sea
Gorebyss - Route 15, Melemele Sea
Shelgon - Kala'e Bay
Salamence - Route 3
Ambipom - Poni Plains
Lopunny - Poni Grove
Happiny - Route 1, Route 4, Route 5, Route 6, Lush Jungle, Hau'oli City Shopping District, Mount Hokulani, Poni Grove, Seaward Cave & Wela Volcano Park
Lucario - Poni Grove
Golurk - Haina Desert
Pawniard - Route 17
Volcarona - Lush Jungle
Fletchinder - Route 8, Wela Volcano Park
Toucannon - Route 11, Poni Grove & Poni Plains
Mareanie - Route 9 & Melemele Sea
Salazzle - Lush Jungle & Wela Volcano Park
Hakamo-o - Vast Poni Canyon
In some areas of The Alola Region, there is usually natural weather. When these adverse conditions are in effect, the game with shift to a different method of SOS Battles called Weather Battles. With these battle, certain Pokemon will appear as an SOS Pokemon, one that usually doesn't come when called upon in regular wild encounters like the Pokemon listed above. In these specific areas as well, if there isn't natural weather, a player can use the corresponding weather causing move in battle to activate a Weather Battle and these given Pokemon. But, as mentioned, it must be in one the areas that usually have weather.
Exclusive Weather SOS Pokemon
Poliwhirl - Malie Garden
Poliwrath - Malie Garden
Politoed - Malie Garden
Catsform - All Weather Areas
Gabite - Haina Desert
Vanillite - Tapu Village
Vanillish - Mount Lanakila
Goomy - Route 17 & Lush Jungle
Sliggoo - Exeggutor Island