Niantic's mobile sensation, Pokemon GO, is no stranger to large events and huge content updates. Every time new Pokemon are added to the game, fans get wild with excitement. Events in the game and content updates typically mean many good things, but one stands out above all: shinies. Each event typically has limited time only shiny Pokemon to catch, meaning they're gone forever after the event ends, so catch them while you can!

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While this makes wanting to catch 'em all more difficult, there are different categories to shiny Pokemon in Pokemon GO. While there are some Pokemon that feel impossible (or are impossible) to catch, they can be split into a few categories.

10 Costume Variations

pokemon go halloween event bulbasaur squirtle pikachu and charmander in halloween costumes walk through town on autumn day sunset

A couple of Pokemon are gifted with the opportunity of having costumes during events. Most of these costumes are simply hats, due to most Pokemon not having bodies capable of wearing intricate costumes, but anything with a head can wear a hat!

These costume variations are rare on their own, but shiny costume variants of Pokemon are even rarer. Think Detective Pikachu is special? Wait until you see its shiny form.

9 Regional Variants That Are Also Shiny

pokemon alolan vulpix in room with lots of books

Regional variants, such as Alolan Vulpix, are extremely rare on their own, but their shinies are even harder to find. This makes them extremely rare and coveted. Having a regional variant that's also a shiny proves how dedicated a player is in their journey to catch 'em all.

Focusing on just Alolan Forms, there are 18 Pokemon that fit the description, all of which are available in the mobile game. These alternatives are already quite rare, and that scarcity is only worsened when it comes to their shinies. When it comes to Galarian Forms, more than 10 have been introduced to Pokemon Go.

8 Shiny Legendaries

pokemon ash and pikachu getting startled by zacian

Legendary Pokemon are called legendary for a reason: there's typically only one of them in the game's lore. Of course, that's fudged a little for the sake of Pokemon GO, but legendary Pokemon are god-like creatures with insane power.

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These one-of-a-kind monsters are hard to find and catch, let alone find the colorful shiny variants of them. Catching one shows that trainers are trusted by these legendary and powerful beasts.

7 The Accidental Shinies

pokemon go shiny clefairy with green ears

There are a few Pokemon with shiny variants that weren't supposed to get them yet. Such as Clefairy or Abra, whose shinies dropped way before they were supposed to, so players lucky enough to have caught them before their ban from the wild are extremely lucky. These Pokemon weren't supposed to get shinies, at least for a while, so these leaks may be the rarest in the game ever.

6 Any Evolved Pokemon

pokemon sobble evolving

Pokemon that can evolve and also have shiny forms have evolutions with shiny forms as well. Something to note about Pokemon who can evolve is that their original form has to be shiny in order for their evolution to be as well. Also, Pokemon that evolve from others that are found in the wild will not be shiny, they have to evolve from an already shiny Pokemon to be shiny.

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This means the fastest way to get a shiny evolved Pokemon for players is to mass breed Pokemon, as eggs have a chance to hatch into one of these rare variants.

5 Shuckle

pokemon shuckle attack flying through purple void

Now that categories of shinies are out of the way, individual shiny Pokemon are rare too, specifically event Pokemon like shiny Shuckle. Right before the Safari Zone event, shiny Shuckle was released. Meaning that people who weren't paying attention to the upcoming event had to specifically be aware that shiny Shuckle was coming out.

Watch out for events, and the surrounding mini-events around them to be sure to catch any limited-time-only shinies!

4 Yamask

pokemon yamask floating under ceiling

The spooky mummy Pokemon, Yamask, had a shiny variant available for a limited time around Halloween 2020. This one-of-a-kind fright evolves into the coffin Pokemon Cofagrigus, a powerful ghost-type Pokemon.

Fans are excited to see what scary Pokemon will be given a shiny variant during 2021's Halloween event and if shiny Yamask will make a reappearance.

3 Mewtwo

pokemon mewtwo looking down at camera in blue tree room with purple eyes

Mewtwo, a genetically modified Pokemon, is one of if not the rarest legendaries in all of Pokemon GO. Released only during extremely limited events, not only is the Pokemon itself hard to catch and rare to find, but that means its shiny form is just as elusive as its regular form.

Players with a shiny Mewtwo should be proud of themselves, as they're accomplished trainers with a lot of skill (and time).

2 Unknown

pokemon man lost in space surrounded by hundreds of unknown

While not a legendary Pokemon nor an event-specific one, Unknown has a variant for each letter of the entire alphabet, plus an exclamation point and a question mark. This means there are 28 different Unknown, and 28 shiny Unknown to be found through Pokemon GO. Players who find all 28 variants are true completionists with the dedication to truly catch them all.

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While they aren't as rare as other Pokemon in the game, it will take just as much time catching all the shiny Unknowns as it will to find extremely rare shiny legendaries.

1 Gastly

pokemon gastly looking surprised being held by officer jenny

This shiny Pokemon, and its whole family of evolutions, are very rare to find in the game. Not only do they tend to be "released" only during special events, where players can see and interact with them but not always catch them, but these ghostly Pokemon have a higher catch rate at night.

Not many players want to wander around their town at night hunting Pokemon, so this makes shiny Gastly and its evolutions a rare sight to be seen among Pokemon GO players.

NEXT: Pokemon Go: The 15 Best Gen 3 Pokemon - Ranked