Legendarys

Legendary and Mythical Pokémon.
To obtain legendaries and mythicals, like the other Pokémon, you don't need other Pokémon to obtain them. Legendaries and Mythicals spawn in time based events. Those who have a shiny Hoopa, either by bashing lucky and finding a SHoopa or just by merely maxing out their levels have a fourth move named 'Summon'. This will spawn any Legendary or Mythical. It cannot be chosen what can and can't spawn.

Where to find them

Articuno: can be found in the snow biome, near to where the Icy Rock is. If you spawn as a water-type Pokémon and look behind you, there will be a few steps leading to a snowy biome with white trees. Carry along the path to come across a left and a right. Articuno spawns on either of these sides but most times by the frozen waterfall. The suggested Pokémon to use when attempting to get Articuno is 'Ash-Greninja' due to it's speed and its spawn location.

This Pokémon spawns in the icy biome.

Zapdos: can be found in the acid parkour, near to where Zubat spawns. If you spawn as a poison-type Pokémon you will be able to jump across some pipes to reach the area where it spawns. The suggested Pokémon to use when attempting to get Zapdos is 'Zubat' due to it's very close spawn location and because it's at the start of the list and can be easily found.

This Pokémon spawns on the small beach, by the secret elevator.

Moltres: can be found next to the volcano, near to where all fire-types spawn. If you spawn as a fire-type Pokémon and exit the volcano, Moltres will either be right in front of you or to the west of the volcano. The suggested Pokémon to use when attempting to get Moltres is Charmander due to it spawning in the volcano and being at the top of the list. Though Torchic has a higher speed, it is harder to find when trying to access a fire-type fast.

This Pokémon spawns inside the volcano.

Lugia: can be found in the water dimension which can be accessed through the portal in the rock quarry. This quarry is opposite to the east side of Meowth's Mad Deals in the Black Oak Community. It can be found by the crystals, or if you take a left by the spiral tower, there will be a mini underground moon shrine to which Lugia can also be found. The suggested Pokémon to use when attempting to get Lugia is 'Ash-Greninja' due to it spawning in the ocean by the rock pool and being very easy to access.

This Pokémon spawns in the Rotom-Town.

Ho-Oh: can be found next to the volcano, near to where all fire-types spawn. If you spawn as a fire-type Pokémon and exit the volcano, Ho-Oh will either be right in front of you or to the west of the volcano. The suggested Pokémon to use when attempting to get Ho-Oh is 'Charmander' due to it spawning in the volcano and being at the top of list for an easier access.

This Pokémon spawns inside the volcano.

Celebi: can be found at the top of the Big Tree, near where all fairy-types spawn. Celebi can be found on the mini platform inside the atop of the Big tree. The suggested Pokémon to use when attempting to get Celebi is 'Togepi' due to it spawning right inside the tree. Easily jump out and begin climbing the tree til you reach the last platform and Celebi will be waiting there.

This Pokémon spawns in the Rotom-Town.

 Regirock : is currently unobtainable.

 Regice : is currently unobtainable.

 Registeel : is currently unobtainable.

Latias & Latios: can be found in the rock pool by the water portal which leads to the water dimension. They spawn anywhere in the pool. The suggested Pokémon to use when attempting to get either of these Pokémon is 'Ash-Greninja'. It spawns right next to the pool, and has a little speed to get there quicker.

These Pokémon spawn on the top of the rocky peak by the diamond sewerage.

Rayquaza: can be found at the end of a parkour made of clouds. These clouds only appear when Rayquaza spawns and disappear after 10 minutes. Climb to the top of the Big Tree to access these clouds and do the parkour. A speedy Pokémon such as 'Ash-Greninja' are recommended for this since some jumps are quite high and distant.

This Pokémon spawns on the top of the rocky peak by the diamond sewerage.

Jirachi: can be found on top of the Axe-Tree near where the portal occasionally spawns. It spawns anywhere on top of it. The suggested Pokémon to use when attempting to get this Pokémon is 'Bulbasaur' as it spawns close to the Axe-Tree.

This Pokémon spawns in the rocky grounding near the rocky peak.

Deoxys: can be found across the rocky bridge. Any water-types spawn near the bridge. Simply climb the ground rock and do the parkour. Go around and climb up the ladder and go across the rocky bridge to meet yourself with Deoxys. The suggested Pokémon to use when attempting to get this Pokémon is 'Ash-Greninja' since it has high speed and spawns in the water.

This Pokémon spawns in the Rotom-Town.

Rotom: can be found in the Haunted Mansion by the volcano in any of the rooms. The suggested Pokémon to use when attempting to get this Pokémon is 'Gastly' since it is very easy to find on the list and spawns inside the mansion.

Despite being a special, Rotom is still part of the Legendary/Mythical spawner.

This Pokémon spawns on the beach.

Uxie, Mesprit & Azelf: can be found in the Creations of Arceus cave. All 3 can be found in the mini puddle upon entering the cave. To trigger the cave door to open, say 'Lord Arceus' WITH the each word being capitalised, or the cave won't open.

These Pokémon spawn in the Rotom-Town.

Dialga & Palkia: can be found on top of the temporal tower in the purple portal that appears in certain spots around the map.

Giratina:can be found at the distortion world on top of the temporal tower in purple portal that appears in certain spots around the map.

Mega Stones