https://www.polygon.com/2018/10/24/18013886/pokemon-go-shiny-shinx-raid-battles

The odds are against anyone trying to find a shiny Pokémon in Pokémon Go — unless you’re hoping for a shiny Shinx, a gen-four Pokémon that’s now in the game. Numerous players worldwide are sharing the sparkling Shinx they’ve caught just days into its availability, a huge surprise about this otherwise hard-to-find Pokémon.

Shinx is an electric-type quadruped (and it’s one of Sinnoh’s cutest Pokémon), appearing infrequently in Pokémon Go thus far. It’s most readily found in Raid Battles, along with the occasional 10-kilometer Egg. Wherever they’re getting it from, people are surprised to see the Shinx they’ve just captured as a bright-yellow cub, instead of the blue one it usually is. That a fourth-gen Pokémon already has an obtainable shiny form is already a big deal, but the amount of people sharing their special finds is a particular surprise.