Pokémon GO Trainers will be delighted to know that a new surprise awaits them in-game as newly discovered Pokémon sizes have been introduced to the game, with selected pocket monsters appearing in XXS and XXL sizes. Developer Niantic also teased plans for more Pokémon monsters and other sizes to be presented later after appropriating UI changes to the Pokédex.
As of writing, Trainers can explore the open world and look out for a few Pokémon appearing in the wild in these sizes, which Niantic named three Pokémon available in the new XXS and XXL sizes: Mawile, Mightyena, and Poochyena. With each of these Pokémon now encountered in the wild, there’s a chance that Trainers may encounter them in their Shiny forms.
19th January 2023 Update: We've updated this news article to confirm that all Pokémon featured in Pokémon GO will have XXS and XXL sizes available, according to developer Niantic. Original reporting continues below.
Furthermore, should Trainers spot either of these Pokémon in the wild, they will see new animations for the XXS and XXL-sized Pokémon, and their sizes will appear more visibly on-screen. Niantic provided an in-game comparison, alongside their standard dimensions, of how the XXS and XXL Pokémon appear during encounters or adventure activities.
This means when encountering Pokémon in the wild, their size and appearance will be recorded in the Pokédex. Notably, the Pokédex will now display information on the caught Pokémon by weight and size, featuring the three announced Pokémon.
And to celebrate this monumental feature for Pokémon GO, if Trainers catch an XXS or XXL-sized Pokémon, they will be greeted with a celebratory message for breaking an in-game size record. This will also expand to Pokémon previously caught in XS or XL sizes; however, Trainers will need to catch any three Pokémon mentioned above for the size record message to appear.
As Niantic plans to introduce more Pokémon appearing in XXS and XXL sizes, the new update has seen some Pokémon reflecting their sizes in the Pokédex, including Magikarp and Pumpkaboo. Additionally, some Trainers reported that the update would extend to all Pokémon previously caught; however, Niantic has yet to provide confirmation.
Lastly, Trainers reported the availability of new medals for catching either extremely small or large Pokémon. According to one Twitter user, there are medals for catching 100 XXS and XXL Pokémon, which appears to include previously caught Pokémon. That's everything we know about the new XXS and XXL sizes arriving in Pokémon GO (for now). So explore the wild and encounter Mawile, Mightyena, and Poochyena in these sizes on your adventures.