April Fools' Day

April Fools' Day was an event in Pokémon GO that took place between March and April in 2018, to celebrate real-world.

Features
The most recognizable feature of this event was changing regular sprites of Pokémon (static raster graphics of 3D models) into 8-bit sprites known from original Pokémon games.

Featured Pokémon
Murkrow had increased spawn rates in the wild (and from Incense, Lure Module):

Shiny Murkrow were released with the start of the event:

News banners
Banners for in-game news changed during the event, portraying the Pokémon as 8-bit sprites. 