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The player and partner encounter Xatu
Xatu (Japanese: ネイティオ Natio) is a non-player character in Pokémon Mystery Dungeon: Red Rescue Team and Blue Rescue Team.
In the games
After Zapdos is defeated at Mt. Thunder, Alakazam suggests that the player goes to speak with Xatu to see if he knows why the player became a Pokémon. After climbing up Great Canyon to the Hill of the Ancients, the player and partner find Xatu there staring at the sun. After trying to get his attention, they decide to either tickle or attack Xatu, both of which end with Xatu revealing who he is (before he is actually attacked in the latter case). He knows that the player was a human, and that the player's transformation and the natural disasters are linked. Xatu's words on the matter are overheard by Gengar, who uses this knowledge to make trouble for the player and partner.
After the player and partner defeat Groudon, Xatu telepathically announces to everyone in Pokémon Square that a falling star is heading towards the planet. He states that their only hope of stopping the falling star is to speak with Rayquaza high above the clouds. To this end, Xatu works with Alakazam to create a Teleport Gem, receiving help from a Ghost-type Pokémon who immediately leaves afterwards, apparently crying. After the player and their rescue team go to Sky Tower and confront Rayquaza, Xatu celebrates their victory along with the other Pokémon who had gathered at the Hill of the Ancients.
After meeting Spinda and receiving the Clear Wing, the player takes it to Xatu and asks about the mirage Pokémon. Xatu knows little about the Pokémon in question, but he recalls three Pokémon that are tied to eruptions, thunder, and the north wind, said to be shadows of the mirage Pokémon. He says that they can be found at the "Three Fields" to the northwest, and he directs the player to Fiery Field as the first step in their quest to meet the mirage Pokémon.
After the team recruits Lugia, Xatu is seen at the team base on its way to shop at Pokémon Square. Blastoise arrives and reports that it found a new cave to the northeast of Mt. Thunder, filled with mysterious creatures that it doubts are even Pokémon. Xatu names this new dungeon Meteor Cave, stating that it was created when a piece of the destroyed meteor crashed into the mountainside.
In the manga
Xatu in Pokémon Mystery Dungeon: Ginji's Rescue Team
In the Pokémon Mystery Dungeon: Ginji's Rescue Team manga
Xatu appeared in I Want to be Human Again!.
For more information on this Pokémon's species, see Xatu.