1926
In Yoshi's Cookie for the SNES, defeating all four characters in VS. mode unlocks a set of what the game calls "new versions" of competitors. Note that the green Mario-like character is explicitly not Luigi, but a "new version" of Mario.
1928
Unique official artwork of penguins seen in a wallpaper provided on Nintendo of America's former site for Mario Kart: Super Circuit.
1929
The actor playing Mario in the North American commercial for Super Mario Sunshine during a break from filming, as well as his head and glove props.
1930
Donkey Kong and Diddy Kong performing on stage at Nintendo Space World 2000.
1931
Extremely rare flagless front-facing Koopa Troopa and Boo artwork for Mario Party, found in the British Nintendo World magazine. "Flagless" refers to the fact that all commonly available Mario Party Koopa Troopa artwork depicts him holding a flag.
1932
Mario drawn by Shigeru Miyamoto in 2003.
1933
Promotional photo by Nintendo of America of Donkey Kong preparing to deliver a truck full of Donkey Kong 64 cartridges to Blockbuster locations.
1934
Illustration of Mario and Bill Gates from a TIME Magazine article about the rivalry between Nintendo and Microsoft.
1935
Toadette's transformation into Peachette upon collecting a crown in New Super Mario Bros. U Deluxe may be a reference to Yoshi's ability to transform into Mario, Luigi and Wario by picking up their hats in Super Mario 64 DS.
1936
In the manual for Tetris & Dr. Mario for the SNES, Dr. Mario exhibits a disproportionately panicked reaction to the scenario of receiving a J piece after a Z piece in Tetris.
1937
Comparison between Weird Mario's sprite in Super Mario Maker seen in the announcement trailer at E3 2014 (left) and the release version of the game (right).
1938
Illustration of Mario from the cover of an issue of the Australian Hyper magazine.
1939
The unreleased "Donkey Kong's Music Play" for the Famicom, shown in a 1983 Nintendo promotional handout. This screenshot shows the "Donkey Band" Karaoke mode.
1940
Illustration from the British Club Nintendo newsletter. Princess Peach and Toad are fleeing from Fareham, a town in Hampshire, England.
1942
Drawing of Raccoon Mario by Shigeru Miyamoto, displayed in a Japanese Mario memorabilia collection.
1943
Previously unknown instance of Big Yoshi artwork found by Twitter user @PieMehker on an extremely rare Super Mario RPG trading card. Previous developments: twitter.com/MarioBrothBlog… twitter.com/MarioBrothBlog…
1944
Dutch and Swedish Mario from a German Club Nintendo calendar.
1945
Artwork from the bottles of the two different varieties of officially licensed Super Mario Bros. shampoo.
1946
An image of Mario being projected onto the side of a building in New York during the GameCube launch on November 18, 2001. To celebrate, Nintendo organized a "Cube Club" event with celebrity guest Lil' Kim.
1947
Renders of Bowser from the Prima official guide for Super Mario Galaxy.
1948
The packaging of the licensed "Radio Boy", a Game Boy-shaped radio, features artwork of an Eerie, a ghost enemy from Super Mario World, listening to the device. Unlike the Eeries in the game, this one is colorful, as though it was not a ghost, but rather still alive.
1949
During FLUDD's introduction cutscene in Super Mario Sunshine, we can see a line denoting the operating system in the upper left. FLUDD appears to be running "O-Y-OS Version 7.01 Service Pack 7.1" The O-Y presumably stands for "オヤ" ("Oya"), E. Gadd's first name in Japanese.
1950
Close-up look at the wanted posters appearing in various places in Paper Mario: The Thousand-Year Door. Of note is that while the first two criminals each have a bounty of 8,000,000 dollars, the last one has a bounty of 8,000,000 cents.
Additional obscure Mario content for suppermariobroth.com.
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