Mario, Magikarp and the Pretend Pikachu: the costume promos

The poncho line's closest relatives are the Pretend cards, where the costume is the whole body. The series opened at a store opening, like the ponchos: for Pokémon Center Hiroshima on June 26, 2015, a Special Box carried Pretend Magikarp Pikachu (150/XY-P) and Pretend Gyarados Pikachu (151/XY-P), Pikachu zipped inside a fish. The Gyarados is the shiny red one, naturally. These were the first of the costume cards printed as Full Arts, the format every later box would use.

In the Sun & Moon era the joke turned villainous. The Pretend Grunt Pikachu Special Box carried Pretend Team Skull Pikachu and Pretend Grunt Pikachu (013 and 014/SM-P), and in 2018 the Team Rainbow Rocket campaign produced seven Pretend Boss Pikachu (191 to 197/SM-P), one dressed as the boss of each villain team: Rocket, Aqua, Magma, Galactic, Plasma, Flare and Skull. Between the two, Pikachu had cosplayed the entire criminal history of the series.

And then there is the crossover. The Mario Pikachu and Luigi Pikachu Special Boxes each held two cards of Pikachu in full Nintendo plumber dress, cap, moustache and overalls: 293 and 294/XY-P for Mario, 295 and 296/XY-P for Luigi. The costume habit outlived the ponchos in the stores themselves: the Pokémon Center Tokyo DX opening in March 2018 issued Hakama Pikachu and Firefighter Pikachu in its Special Box (208 and 209/SM-P) and Gentlemanly Pikachu and Cherry Blossom Afro Pikachu at the opening itself (210 and 211/SM-P).