Trio master

Trio master is a fan term referring to a Pokémon that, in some way, oversees a Legendary trio of Pokémon.

The trio master and the trio itself may relate in different ways. For example, Lugia is the trio master of the Legendary birds; it is the only one who can quell their fighting when Lawrence III captures one of them in The Power of One.

Catching trio masters

In the games, the trio master sometimes will require that the members of its Legendary trio be caught beforehand. There has been other ways from which the trio master is referred to as such though.

Pokémon Crystal

In Crystal, Ho-Oh cannot be caught until all three of the legendary beasts have been caught in the same game.

Pokémon Diamond, Pearl, and Platinum

In Diamond, Pearl, and Platinum, Regigigas will not awaken unless the player has the legendary golems in his or her party. Conversely, an event Regigigas unlocks the legendary golems in Platinum.

Pokémon HeartGold and SoulSilver

In HeartGold and SoulSilver, Rayquaza is only obtainable after both Kyogre and Groudon have been obtained in the same game, which requires trading.

Pokémon Black and White

In Black and White, Landorus is only obtainable after both Tornadus and Thundurus have been obtained in the same game, which also requires trading.

Pokémon Black 2 and White 2

In Black 2 and White 2, Regigigas will not awaken unless the player brings the golems to its resting place, Twist Mountain.

Pokémon X and Y

In X and Y, the name of the cave where the legendary birds retreat after being encountered 10 times roaming in Kalos, alludes to Lugia.

Pokémon Omega Ruby and Alpha Sapphire

In Omega Ruby and Alpha Sapphire, Regigigas can be encountered in the Island Cave if the player has Regice, Registeel, and Regirock in their party.

Landorus can only be encountered while Soaring if the player has both Tornadus and Thundurus in the player's party.

Other references to trio masters

• In Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team, the legendary birds must all be befriended and must create the Vortex Stone before the player can enter Lugia's dungeon, and before encountering Ho-Oh, the three legendary beasts must contribute their power to create the Rainbow Wing.
• In Pokémon Mystery Dungeon: Explorers of Time and Explorers of Darkness and Explorers of Sky, Aegis Cave has four bosses: Regirock, Regice, Registeel and Regigigas. The golems must be beaten first before Regigigas can be challenged at the end of the cave.
• In order to get Ho-Oh in Pokémon Colosseum, the player must first capture and purify all the Shadow Pokémon, which includes the legendary beasts, as one of the two requirements.
• In Pokémon XD, the legendary birds are encountered after the player encounters Shadow Lugia.
• In Pokémon Ranger: Shadows of Almia, the player needs to befriend all the Pokémon in the regional Browser, which includes the legendary golems, to battle Regigigas. The golems themselves are also required in order to open the door to its domain.
• In Pokémon Ranger: Guardian Signs, the player needs to befriend all 300 Pokémon in the regional Browser, which includes the three legendary birds, to battle Lugia.

Relationship with their trio

Trio master	Legendary trio
	Relationship
Lugia	Articuno		Zapdos		Moltres
	Lugia is the only one who can end the Legendary birds' conflict, as seen in the second movie.
Ho-Oh	Raikou		Entei		Suicune
	After the three Pokémon perished in the fire at the Burned Tower, Ho-Oh revived them.
Rayquaza	Kyogre			Groudon
	Due to it ending the other two members' fight in Emerald, Rayquaza serves as the internal master of the weather trio.
Regigigas	Regirock		Regice		Registeel
	Regigigas will awaken when the three Legendary golems are brought to its residence. It is also said that it built statues made of clay, ice, and magma.
Arceus	Dialga		Palkia		Giratina
	According to legend, Arceus created all three members of the creation trio after creating the universe, in order to balance the dimensional-aspect world.
	Uxie		Mesprit		Azelf
	Arceus also created the lake guardians, which represent spirit, before it fell into eternal slumber.
Landorus	Tornadus			Thundurus
	Landorus punished Thundurus and Tornadus for bringing mass destruction with their thunder and wind storms. As such, it serves as an internal trio master, like Rayquaza. It cannot be battled until both of the latter are brought to the Abundant Shrine.

Trivia

• Arceus is the only trio master that is related to more than one Legendary trio.
  • Arceus is also the only event-exclusive trio master.
• Lugia and Regigigas are the only two trio masters who were not present in the same generation as their trio. Also, each was introduced in the generation directly after the generation its trio was introduced. This also makes their trios the only ones that did not have a known trio master in the generation they were introduced in, then gain one later.
• The Tao trio is the only trio group without a known trio master.
  • However, according to Drayden and Ghetsis in Black 2 and White 2, Kyurem is the remainder of the original dragon after it was split into two. Also, Kyurem shifts into its two Formes by fusing with either Reshiram or Zekrom. In this case, Kyurem could be an internal trio master, much like Rayquaza and Landorus.
• Regigigas and Rayquaza (as well as Arceus without a Plate) are the only trio masters that do not share at least one type with any other members of their trios.
• Landorus is the only trio master that is not genderless.
• Rayquaza is the only trio master capable of Mega Evolution.