Nintendog

Nintendog is the name of any puppy character from Nintendo's Nintendogs game series. Nintendogs are named after their debut game, which in turn is a portmanteau of "Nintendo" and "dog." Nintendogs have appeared in a few games related to the Mario franchise.

WarioWare series
Nintendogs appear in the microgame Nintendogs in WarioWare: Smooth Moves, where the player has to high-five the puppies. They also appear in a similarly named microgame in WarioWare Gold, where the player must rub them.

Super Smash Bros. Brawl
A white Labrador Nintendog became an Assist Trophy in Super Smash Bros. Brawl. When it is activated, it will distract the players by covering most of the screen and start clawing and barking, although it only worked on actual players. Nintendogs also appear as stickers and a trophy.

Super Smash Bros. for Nintendo 3DS / Wii U
In Super Smash Bros. for Nintendo 3DS and Super Smash Bros. for Wii U, the Nintendog returns as an Assist Trophy, though in this game it is a French Bulldog. A number of Nintendogs also appear on the Living Room stage in Super Smash Bros. for Nintendo 3DS.

Super Smash Bros. Ultimate
In Super Smash Bros. Ultimate, the Nintendog returns as an Assist Trophy, though in this game it is a Toy Poodle. As the Living Room from Super Smash Bros. for Nintendo 3DS returns, a number of Nintendogs also appear. All three Nintendogs that have appeared as Assist Trophies in the series appear as spirits.

Super Mario Odyssey
In Super Mario Odyssey, a Nintendog, specifically a wearing a fedora, is a recurring character. Its model is taken directly from Nintendogs. Mario can play fetch with the dog by throwing Cappy, whom the Nintendog will then retrieve. It shows up in various kingdoms after the kingdom's boss has been defeated. The Nintendog appears in the Sand Kingdom, Seaside Kingdom, Metro Kingdom, Moon Kingdom, and Mushroom Kingdom, where it leads players to buried coins and Power Moons. Furthermore, in the other kingdoms left, the Nintendog appears inside the Odyssey after finishing the game at least once. A Toad in the Mushroom Kingdom claims to be the Nintendog's owner. Also, if Mario falls asleep, the Nintendog will fall asleep next to him. The Nintendog is also seen in attendance at the wedding of Bowser and Peach. The Nintendog's fedora cannot be removed, possibly to prevent Mario from potentially capturing it.

Similarly, there are many Mario references in the Nintendog series. The player can find hats that are the same as Mario's and Luigi's, as well as various toys. These include Mario, Princess Peach, and Bowser karts (designed with their Mario Kart DS kart style), which can be driven around the room, as well as Mushroom and ? Block toys to throw around. Additionally, the music played while driving the toy karts is heard from courses in Mario Kart: Double Dash!!

Super Smash Bros. for Nintendo 3DS / Wii U
Red indicates exclusive to the Nintendo 3DS version.