Tandemaus will evolve into one of two forms of Maushold, Family of Four or Family of Three, with a 1/100 chance of evolving into Family of Three Maushold.
Tandemaus is a Pokémon comprising two separate mouse-like rodent Pokémon which work together as one, much like Exeggcute or Falinks. Each individual is small, white, and bipedal, and has a spherical head with large ears and stubby limbs with large paws. Each one also has two black beady eyes, a tiny black nose with short whiskers, and a long tail which curls up and ends with a bulbous tip. One of the pair has a light-gray patch of fur surrounding its chest which resembles a shirt, while the other has a light-gray patch of fur surrounding its legs, which resembles a pair of pants. When they open their mouths, which take up over half of their faces when fully open, a single upper incisor can be seen on the insides of each one.
The pair that forms Tandemaus sticks together no matter what. They exhibit great teamwork: they share any food they find equally within the pair, and they build their nest together using materials they've gathered with their incisors. Tandemaus's Evolution into Maushold is considered somewhat of a mystery, as the little individuals that form the group seem to appear out of nowhere.
The form of Maushold that Tandemaus evolves into is determined based on its encryption constant, with a 99% chance of it evolving into the Family of Four form and a 1% chance of it evolving into the Family of Three form. This is not the case for wild Maushold encountered in Tera Raid Battles, as these will have a predetermined form (Family of Three in 4★ raids or Family of Four in 6★ raids) regardless of their encryption constant value.
In The SOS is from Tandemaus?, the image of a Tandemaus was seen on Liko's Rotom Phone. In the episode, a Maushold was initially mistaken for a Tandemaus until the two little ones were discovered.
Tandemaus, the Couple Pokémon. A Normal type. They use their sharp front teeth to bite off and carry various materials to build their nests. They will always be found in pairs, never alone.
Unlike every other Pokémon that evolves via leveling up, there won't be the typical Evolution animation if Tandemaus levels up to level 25 or higher in a battle it was not sent out in. In such a scenario, it is also impossible to cancel the Evolution.
Because it must specifically level up in battle, Tandemaus is the only Pokémon that can be locked out of Evolution upon reaching level 100 since the Rare Candy was updated to allow Evolution at the highest level in Generation VIII.
Origin
Tandemaus seems to be based on a pair of mice. Its appearance resembles dollhouse figurines such as the Japanese doll line Sylvanian Families.
Name origin
Tandemaus may be a combination of tandem and Maus (German for mouse).
Wakkanezumi may be a combination of 輪っか wakka (loop) and 鼠 nezumi (mouse).
This Pokémon article is part of Project Pokédex, a Bulbapedia project that aims to write comprehensive articles on each Pokémon species, as well as Pokémon groups and forms.
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For other sprites and images, please see Tandemaus images on the Bulbagarden Archives.
