The Mystery Box is a new element to Pokémon GO utilised to access the 808th Pokémon, Meltan.

The Mystery Box is only obtainable through one way. To get it, you need to connect your Pokémon GO game to the Nintendo Switch titles, Pokémon: Let's Go, Pikachu! & Let's Go, Eevee! or Pokémon HOME. When you transfer a Pokémon from GO to Let's Go/HOME, you will receive the special Mystery Box.

The Mystery Box, when opened, provides a special bonus. For 30 minutes (or more during bonuses), you will have the ability to find the Mythical Pokémon Meltan and catch it. It spawns on average of one Meltan every 1.5 minutes.

When the time runs out, Meltan will stop appearing in the wild. However, you can re-open the box after waiting for 3 days. After that time, send another Pokémon to Let's Go and you'll be able to open the box once more.

Unique Special Research will also take place once opened focusing on Meltan. This opens up this Winter

Melmetal is the evolution of Meltan. It can only evolve from Meltan in Pokémon GO by using 400 Meltan Candy. This means you need to utilise the Mystery Box repeatedly in order to capture enough Meltan to evolve it into Melmetal