You normally have a one in 4,000 chance of finding a Shiny Pokémon, but Pokémon Ultra Sun and Moon change the odds by giving you another sure-fire way to find Shinies, and players have been collecting them by the truckload. To Shiny hunt, you’ll need to beat the base Pokémon Ultra Sun and Moon game. Then it might be a good idea to go to Heahea City on Akala Island and into the Game Freak building, which can be found at the right of the Pokémon Center. Here, you can change your control input while traveling through Ultra Wormholes.
Once you’ve got that out of the way, you’ll want to Charizard Glide straight to the Altar of the Moone, which is located at the top of Poni Island, and enter the warp hole there. Once you start losing speed and start getting gently pulled into wormholes, you’ll want to look out for white wormholes with rainbow edges. That’s where you’ll have a chance of finding a Shiny. With this method, it could take as little as 15 minutes to find a Shiny Pokémon.
Source: Kotaku
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