Pokemon Go fans have a new quest: Shiny Magikarp.

The popular game has an event going on right now that honours water-type Pokemon, and as part of an effort to get people playing Pokemon Go, the app is offering up highly coveted shiny Pokemon. These have never been spotted in the app before and are obviously hard to find. They can transform and have different colours than standard Pokemon. So, if you happen to catch any shiny Magikarp, you're doing well.

They are collector's items that evolve into powerful red Gyarados, which are featured prominently in Pokemon Gold and Silver. Although spotting a golden Magikarp won't be easy, you should keep in mind that the Water Festival makes water-type Pokemon of all kinds more common everywhere. Nevertheless, it only has a discovery rate of 220 standard Magikarp to one shiny, according to Kotaku.

You'll need to do some leg work to catch shiny Magikarp, but once you do, you might as well pick up this hat that Niantic, the game's developer, has begun offering in the in-game shop. Niantic said its special event ends on 29 March at 4 pm ET.