Foster's Home for Imaginary Friends episode The Buck Swaps Here
May 18, 2007
In the second episode of season 5 (Episode #55), there are two men carrying a large mirror - one is tall in green overalls and a blue shirt, the other short and plump with red overalls and a blue shirt. This makes the two resemble the Mario Brothers. Also, when attacking the robber, they shout with Italian accents.
Foster's Home for Imaginary Friends special episode Destination Imagination
May 18, 2007
In a scene in the second 90-minute movie of the series, corresponding to sixth through eighth episodes of season 6 (Episodes #72-74), Mac and the imaginary friends he foster gang enters a zone very similar to a level from Super Mario Bros. with plants coming out of pipes similar to Piranha Plants and snails retracting in their shells in the same style as Koopa Troopas. Mac also hits a block from below, making a fruit come out, and then picks it up becoming twice as high and capable of breaking brick blocks, much like the Super Mushroom from the original game. Eduardo then gets another fruit and starts flashing, becoming invincible for a short time, just like the Starman power up from the game. The section ends with the team entering a pipe and then being shot away from a cannon, just like happens in Super Mario 64.
The creators of Foster's Home for Imaginary Friends held no right over Nintendo's Mario, but they only included minor references to the games.