Evolution

Like the main games and the Mystery Dungeon games, Pokémon have the ability to evolve. This changes their species and allows them to be even stronger and increases the chance of having a Best Link with the Warlords

Evolving Pokémon

Method
Evolving Pokémon is relatively simple. Like in the main games, it's done based upon the level. However, this level isn't the strength level but the link level between the Warlords and their Pokémon. As such, if the Warlords has a low possible link to the Pokémon, then it will not be able to evolve all the way. Happiness and trade evolutions get mapped to the Link level with a high amount of around 50-70%

However, for item evolutions, there is an extra component. Dotted around the Ransei region, there are various shops where you can purchase the items. These are the same items as within the game. Attach the item to the Pokémon and it will evolve following the battle.

Evolution TypeMethodPokémon
StandardRaise the Pokémon to a specific Stat levelsMost Pokémon
ItemsAttach an item and use in battleClick Here
LinkRaise the link of a Pokémon to a specific level. Done via abilities, battling, Link etc.Igglypuff, Pichu, Chingling, Riolu, Golbat, Munchlax
EnvironmentalRaise the Pokémon to a specific Link % and use them in battle in a specific nationEevee -> Espeon - Illusio
Eevee -> Umbreon - Yaksha
Eevee -> Leafeon - Greenleaf
Eevee -> Glaceon - Nixtorm
Warlords CombatRaise the Pokémon to a specific Link % and battle against a Warlords and defeat itMachoke, Kadabra, Boldore, Haunter, Gurdurr
Evolving Warlords

Method
In addition to Pokémon evolving, many of the Warlords have the ability to "evolve". This evolution causes their appearance to change and also increases the various stats of the Warlords which allow for quicker movement of the Pokémon, more Pokémon to be raised and even a different Best Link Pokémon.

To get the Warlords to evolve, you need to reach an incredibly high Link level with the Pokémon that is classified as the best Pokémon for the Warlords to be tied with. Not all of the Warlords have the ability to evolve, with it mostly being the Warlords who are gold coloured in the menus.