Back in February we had an event for about a month that brought Shiny Meltan into the game and a reduction of time on getting another Mystery Box. Shiny Meltan was only possible to get during that event

While the Hatchaton event was going on, we also simultaneously had a Let's GO Pikachu & Eevee event tied into it which saw an increase of many gen 1 Pokémon and Pokémon like Slugma, Gulpin and Anorith