You may already be familiar with the new SOS battle mechanic in Pokémon Sun and Pokémon Moon. When you’ve completed the first trial in the games, wild Pokémon will start to call upon Pokémon to assist them in a two versus one battle. In one hand, that makes wild Pokémon a little bit more tricky to capture and wild Pokémon battles tougher to beat, but on the other hand this mechanic can also be exploited. When a wild Pokémon calls for help and you defeat the called-upon ally, it can call upon another wild Pokémon to be its ally. As a result this creates a chain; this is called SOS chaining. You can do SOS chaining to get more Effort Value (EV) points, Individual Values (IV), a chance on getting Pokémon with Hidden Abilities, or an increased chance to find a Shiny Pokémon.
Wild Pokémon won’t call for help all the time, and even if the wild Pokémon does call for help, there’s a chance that ally Pokémon won’t appear anyway.
The lower the wild Pokémon’s health is, the more chance the Pokémon will call for help, and each Pokémon has a different call rate. For example, a wild Cleffa has more of a chance to call for help than a wild Fearow (15% > 6%).
When a wild Pokémon calls for a new ally, the ally Pokémon will likely be the same Pokémon family as the caller. Cleffa for example can call for another Cleffa, or a Clefairy as an ally Pokémon. Depending on the caller Pokémon and the conditions during the battle however, different Pokémon can also appear. For example, Cleffa’s call for help can also summon wild Chansey.
It’s important to note that only when there are two Pokémon of the same family on the field and the caller faints, then the ally Pokémon becomes the new caller. Going back to the first example, if Cleffa (the caller) faints while Clefairy (its ally) is still on the field, then Clefairy becomes the new caller for its family. Thus the chain then continues. However, if Cleffa faints while a Chansey is on the field, then Chansey won’t call for Pokémon, thus ending the chain.
Of course not all Pokémon call for help, such as Legendary Pokémon, Island Scan Pokémon or Ultra Beasts. Minior, Mareanie, and Komala also don’t call for help.
It should also be noted that weather can affect your chain. For example if you want to chain a Formantis, and it’s raining, it won’t always be called in. Instead you may get a Goomy or Castform! In certain areas across Alola, if it’s raining or hailing, you may find new Pokémon through SOS calling. These cares are still rare summons though and might require some time to find.
*Important: Note that a chain ends at 255 encounters, similar to how the DexNav capped at a chain of 100 after which the odds reset. Your odds of finding Shiny Pokémon, Hidden Abilities and IVs reset after 255 encounters.
All Effort Values (EVs) gained in a battle are doubled whenever you faint an ally Pokémon. Cleffa gives 1 EV in Special Defense when you knock it out, for example. But when you knock out an ally Cleffa, its Special Defense EVs are doubled to 2. Knock out both Cleffa, and you’ll get 2 * 2 = 4 EVs.
This allows for quick EV training, especially when combined with PokéRus (doubles EVs gained) and the Power Items (e.g. Power Bracer) which add 8 EVs to its respective statistic before SOS or PokéRus is applied. For example, knocking out one Zubat or Rattata (one Speed EV) in a SOS battle when your Pokémon has PokéRus and holds the Power Anklet gives you:
((1 + 8) * 2) * 2) = 36 EVs
Hence knocking out seven Pokémon in an SOS battle (36 * 7) gives you the maximum 252 EVs for that stat. Easy!
In addition to EVs, you can get Individual Values (IVs) very easily through SOS chaining. IVs are hidden number values that determine how good an individual stat is for a Pokémon. If you are looking to get into competitive battling, then this is a great thing to know about! The highest value each stat can have for IVs is 31, and the lowest is 0.
Previously, the best method for IV obtaining was through breeding. In XY the Poké Radar made its return. This tool was used for Shiny hunting, however it also helped obtain IVs. Every 20 chains, you would be guaranteed to have one perfect IV. With the introduction of SOS chaining, you can do the same! It is much easier though, because now, every 10 chains gets you a perfect IV on that Pokémon. You have a higher chance of getting 5-6 IVs after you reach a chain of 40. The odds for IVs are:
|Chain Length||No of IVs|
|0-4||No guaranteed perfect IVs|
|5-9||1 guaranteed perfect IV|
|10-19||2 guaranteed perfect IVs|
|20-29||3 guaranteed perfect IVs|
|30-255*||4 guaranteed perfect IVs|
Shiny Pokémon have a higher chance of appearing. However like IVs and Hidden Abilities, Shiny chance is affected by the chain number. The odds for Shiny Pokémon are:
- Chain length of 0 to 69: Not yet known
- Chain length of 70 to 255*: Three extra rolls for a shiny spawn. This will make the game essentially ‘re-roll the dice’, giving you three more chances for a shiny to be called after the 70th encounter of the chain. Thus without the Shiny Charm, your odds become 1/1024, and 1/683 with the Shiny Charm.
Hidden Abilities are abilities that can be obtained through different methods then normal wild encounter. Often these are much more viable competitively and are very useful. For example, Yungoos (and its evolution) has the Hidden Ability of Adaptability, while Spearow gets Sniper. Like past games, there is a new method for obtaining them. In Sun and Moon, SOS chaining is that method. As mentioned above, the chain you have affects the abilities you get. The chances for Hidden Abilities are:
|Chain Length||Hidden Ability Chance|
SOS Chaining Preparation
Before you go to SOS chain, it’s important to prepare! Find below some helpful moves, abilities, and items to help you out for chaining.
Adrenaline Orbs increase the chance for wild Pokémon to call ally Pokémon during battle, so it’s helpful to stock up on a few. You can purchase these in any Pokémon Center Mart, after you’ve beaten the third trial in the game.
Leppa Berries restore any one of your Pokémon’s moves by 10 PP. These items, along with Ethers and Elixirs, are useful if you’re looking to chain for Shiny Pokémon. You can grow Leppa Berries in Poké Pelago.
Note also that using an Item takes up a turn, which is useful when the wild Pokémon fails to call an Ally.
False Swipe and Hold Back are moves that reduce a Pokémon’s health to at least 1 HP. This is useful for increasing the chance for wild Pokémon to call for help. In case you want to chain Ghost Pokémon, you can have moves like Soak to change its type to Water, or identifying moves like Foresight to allow it to hit Ghost Pokémon with Normal-type moves. Alternatively you can get a Pokémon with the ability Scrappy to hit Ghost types with Normal-typed moves. Pangoro is good for this, but it can only be found on Ula’ula Island. It also requires some chaining, as Scrappy is its Hidden Ability. There is an easy way to find out if the Pancham you encounter has this though!
Ability changing moves like Worry Seed can help if you want to check a wild Pokémon’s Ability. This is ideal for when you want to check for Hidden Abilities.
Status-afflicting moves like Spore or Hypnosis are useful to stop caller Pokémon from calling more ally Pokémon. Inflict status when you’ve found the Pokémon you’re looking for and want to capture it with ease.
Generally it might be a good idea to have Pokémon with high-PP moves, so they won’t run out of PP quicker while you’re chaining. Use PP Ups to increase the maximum PP of moves as well!
If you’re looking for specific natures, then lead with a Pokémon with the ability Synchronize. Leading with Synchronize has a 50% chance on finding wild Pokémon with the same nature as the Pokémon with this ability. Abra and Ralts are Pokémon that have this Ability. The lead Pokémon can be fainted as well – it still works! Be sure to keep the Pokémon with this ability on the field whenever a new wild ally Pokémon is called, so that the ally also has a 50% on having the same nature too.
Note: There is actually a bug in the games right now where Synchronize copies the nature of the first slot instead of the on-field synchronizer, if the on-field synchronizer isn’t at the first slot in your Pokémon party. So, when you’re planning on SOS chain Pokémon for a specific nature, you don’t need a Pokémon with Synchronize for every nature.
Having Pokémon with Intimidate, Pressure, or Unnerve on the field can increase the chance on wild Pokémon calling for help.
Soundproof can help avoid moves such as Roar, which could force Pokémon out of battle and breaking the chain. However, if you are higher in level than the Pokémon, then Roar will fail.
Pokémon with Damp can prevent wild Pokémon from using Self-destruct or Explosion in battle, so that it won’t break the chain.
To start chaining, first find whichever wild Pokémon you want to SOS chain with. Once you’ve found it, lower the Pokémon’s health as much as you can without fainting it, which will increase the chance that it will call for help.
Next, use an Adrenaline Orb to make the wild Pokémon nervous and further increase the chance on it calling for help.
Once the ally Pokémon arrives, make it faint, but keep the caller Pokémon on the field. This will allow it to call for ally Pokémon again, beginning the chain. You can then faint the next ally Pokémon, allowing the caller Pokémon to call for help again. If no Pokémon appears or if the caller Pokémon does not call for help, use an Adrenaline Orb again. It will fail, but it will not use one up which is a great turn waster. You can keep doing that on the turn no other ally Pokémon is on the field.
Avoid making the caller wild Pokémon Struggle (when all its moves have 0 PP) when there are no other family Pokémon on its side of the field or else it will faint, ending the battle and chain. Make sure to change the caller Pokémon regularly by fainting the first caller Pokémon when its ally Pokémon of the same family is also on the field. This will make that ally Pokémon the new caller for the same family.
Keep doing this process until you find what you’re looking for, whether it is Shiny Pokémon, Pokémon with Hidden Abilities and good IVs, or gaining EVs for EV training.
Edited by bobandbill, Nick Wilde and Z25.