Legendary Pokémon are Pokémon that are characterized by their rarity and their high base stat totals. They are very difficult to obtain because of their difficulty to locate, high levels, and low catch rates.
A Legendary Pokémon has a chance of spawning after a random time interval between 90 seconds and 210 seconds has elapsed. This chance of spawning depends on multiple factors, including whether Legendary Pokémon can spawn in the different biomes and spawn locations, whether the spawn positions are close enough to players, the amount of terrain that is compatible for a Legendary Pokémon's spawn location, and a base percentage of the Legendary Pokémon spawn attempt failing (30% by default).
A message will be broadcast when one of them spawns. It is possible for more than one of each Legendary Pokémon to spawn in a world, although each individual Legendary Pokémon species has an 80 minute delay after spawning before the same species of Legendary Pokémon has a chance to spawn again.
Articuno, Zapdos, and Moltres spawn when a fully-charged orb that matches their type (orb of frozen souls, orb of static souls, orb of fiery souls) is placed in the centerpiece of their respective shrines. Each type of shrine spawns very rarely in certain biomes. An orb can be charged by having it in the player's inventory while defeating 375 Pokémon; these Pokémon do not have to match the orb's type.
Mewtwo can be obtained by successfully cloning a Mew in a cloning machine.
The following settings related to Legendary Pokémon can be changed in the Pixelmon config file:
- "allowLegendarySpawn": Whether Legendary Pokémon spawn naturally.
- "displayLegendaryGlobalMessage": Whether or not a message appears when a Legendary spawns.
- "legendaryRepeatSpawnTicks": The average delay after a Legendary spawns before the same Legendary can spawn again.
- "legendarySpawnChance": The base chance of a Legendary spawning attempt succeeding if it would otherwise succeed.
- "legendarySpawnTicks": The amount of ticks that will pass before a Legendary attempts to spawn. This delay is randomly between 60% and 140% of the base tick amount that is specified.
- "reusableBirdShrines": Whether or not shrines are reusable after being used.
- "spawnStructures": If disabled, shrines (and Pokémon Centers) will not spawn naturally.
- "spawnBirdShrines": If the above setting is true and this setting is disabled, shrines will not spawn naturally but Pokémon Centers will.
- "cloningMachineEnabled": If disabled, cloning machines cannot be made, making Mewtwo impossible to obtain legitimately.