Dataminers confirmed that 3D assets for the shiny versions of Gen 1 Pokemon have been added to the game. Paired together with the next event in the game which will have the old school Kanto Pokemon, we could possibly see shiny versions of all 151 Pokemon.
To have a shiny means that it has an alternate coloration than their regular non-shiny counterparts. They are also extremely rare, and Niantic is slowly adding Shiny Pokemon to the game since last fall.
Some players knew that something big will happen because many of the sprites had changed. It is also possible that the next week event is a start of a rollout of all the shiny Pokemon. If they release all of the 151 shiny versions at once, it will be a total chaos.
Also, the shiny versions aren’t shown on the overworld map. Players need to tap every Pokemon individually to see if it’s shiny. When the screen opens, the players can look out for a sparkly animation that surrounds the shiny Pokemon.
This also means we’ll need more storage space because it’s already too hard for a lot of Trainers to manage their collection in 1500 slots and many times players don’t know what to delete in order to make space. With this being said, I believe that Niantic will increase the storage space, so we could all enjoy the upcoming shiny event.
We will have more information about the next event in the following days. The Gen 1 event will start on April 10.