This page explains in detail the interactions between the Mario series and the Metal Gear series.
Metal Gear Solid: The Twin Snakes[]
Mario and Yoshi dolls in Metal Gear Solid: The Twin Snakes.
March 09, 2004
Mario
Metal Gear
A Mario and a Yoshi doll can be found in Otacon's lab. Shooting Mario makes the writing "1UP" appear while making the 1-Up sound. Shooting Yoshi causes him to say "Yoshi!"
Psycho Mantis talking about Super Mario Sunshine.
Additionally, Psycho Mantis may mention Super Mario Sunshine during his battle if the player has a save file for that game in the memory card in slot 1.
License[]
Metal Gear Solid: The Twin Snakes was licensed by Nintendo to be released on the GameCube, so Konami was able to include references to Nintendo series, including Mario.