The official Pokémon website has announced more details about the Bulbasaur and Squirtle that will be distributed via Mystery Gift in June 2021.

Get Bulbasaur and Squirtle Capable of Gigantamaxing in Pokémon HOME This June

The mobile version of Pokémon HOME is receiving some useful updates, and you can receive some powerful Pokémon to celebrate.

Sorting your Pokémon in the mobile version of Pokémon HOME is about to become easier than ever with June's update. Look forward to the new Catch Calendar, enhanced Pokédex features, and two special Pokémon that Pokémon HOME users—as well as Pokémon Sword and Pokémon Shield players—will be able to receive via Mystery Gift.

The Catch Calendar feature allows you to view your Pokémon arranged by the dates on which you caught them. This will let you relive memories from your adventures, such as the day you caught your very first Pokémon or the day you finally added a powerful Legendary Pokémon to your team. You can also set specific dates as Anniversaries, such as your birthday or the day you first met a Pokémon that has become special to you.

The updated Pokédex introduces the ability to view Pokémon registered to your Pokémon HOME Pokédex from different angles. You'll be able to get a better look at your Pokémon partners, and you might even discover some new details that you didn't notice before.

To top things off, these new features are being commemorated with special Bulbasaur and Squirtle that you'll be able to receive as Mystery Gifts in both the mobile version of Pokémon HOME and in your Pokémon Sword or Pokémon Shield game. What makes these two beloved Pokémon so remarkable is that they carry the Gigantamax Factor! This pair is a perfect complement to the Charmander you can receive from Leon once you've become the Champion in Pokémon Sword or Pokémon Shield.

Source: https://www.pokemon.com/us/pokemon-news/get-bulbasaur-and-squirtle-capable-of-gigantamaxing-in-pokemon-home-this-june/