The last Pokémon Sun and Moon trailer for October has revealed eight new Pokémon, including the final evolutions of the starting Pokémon, and given hints about the game's structure.

New Pokémon:

• Rowlet's final evolution is Decidueye, a Grass/Ghost type with the trademark move Spirit Shackle (prevents opponent from switching)
• Litten's final evolution is Incineroar, a Fire/Dark type based on a rudo in the lucha libre wrestling tradition. Its trademark move, Darkest Lariat, damages and ignores stat buffs.
• Popplio's last form is Primarina, whose trademark is Sparkling Aria, a move that damages and also heals burns.
• The island guardians are Tapu Lele (Akala Island, Psychic/Fairy, sets "Psychic Terrain" which prevents priority moves), Tapu Bulu (Ula'ula Island, Grass/Fairy, sets Grassy Terrain for healing), and Tapu Fini (Poni Island, Water/Fairy, sets Misty Terrain which affects stat buffs/debuffs). All four guardians share a special Z-move called "Guardian of Alola".
• A new standalone Psychic type called Cosmog was shown, with the Unaware ability
• Alolan Meowth evolves into Alolan Persian, with the same Dark type and Fur Coat or Technician for abilities

The trailer spotlights the creation of the Alolan Pokémon League, and also showed off a battle facility called the Battle Tree. In the Battle Tree, players can team up with and battle against classic series trainers including Cynthia (Diamond/Pearl/Platinum champion), Wally (Omega Ruby/Alpha Sapphire rival), Red and Blue.