2001
In almost all 3D games, Birdo's eyelids are always partially closed, with the eyes never opening wider than the example on the left. The only time Birdo's eyes were ever fully open in a 3D appearance is in a shocked animation used in Fortune Street (middle and right).
2002
In Mario Party 7, several polygons in Birdo's eyes are missing, creating holes that can be seen through. This is the only time in the Mario Party series that a character's model is incomplete in this manner. In total, 10 polygons are missing, resulting in 4 distinct holes.
2003
Mario being intercepted by another, fast-moving Mario during a Japanese educational video meant to teach children the Latin alphabet.
2004
The Japanese name for Toad is キノピオ (Kinopio), usually assumed to be a pun on famous children's book character Pinocchio. Possible evidence that this is the intended reference comes from Super Mario Galaxy, which uses the name "Pinokio" for textures of Toad models.
2005
One of the only known images depicting MarioMotors.inc, a Mario racing game for the Nintendo DS that never passed its conceptual stage. The game's intended main mechanic was the building of custom engines and vehicles through the shaping and connecting of metal chunks.
2006
Graphics used in the Marrymore kissing cutscene in Super Mario RPG.
2007
Size comparison chart of Super Mario World enemies from the 1993 official Nintendo character manual.
2008
Princess Peach reading a story to the Koopalings, from the comic booklet enclosed with Nintendo: White Knuckle Scorin', a 1991 music album released by Nintendo.
2009
I have been informed that an alternate path exists in the mission that avoids the coin I presumed was mandatory. As such, this message is not impossible to see during regular gameplay, but merely extremely difficult. I hope the post is still acceptable.
2010
Correction to the previous Tweet: I had mistakenly claimed it is Mario who is 3D in NSMBU and 2D in Super Mario Maker 2; it is in fact the goal pole itself that is 3D on the left and 2D on the right. I apologize for the error. Thank you to everyone who offered corrections.
2011
Graphic for the hidden Luigi ice sculpture found in a cave in level Frosted Glacier-3, "Fire and Ice", of New Super Luigi U, extracted from the game's data.
2012
The 3D model for Chain Chomps is carefully crafted to appear as circular as possible from almost all angles even when their mouths are open. However, this effect is not optimized for viewing them from above.
2013
Luigi's sprite for getting up from sleeping in the educational SNES game Mario's Early Years: Preschool Fun.
2014
As pointed out by reader @ChiefNeif, the gun is used as a reflection texture for the golf club, being so stretched out that it is not recognizable in-game. However, it is still unclear where the gun image comes from or why it was chosen for this purpose. twitter.com/ChiefNeif/stat…
2015
Landing in this spot of Ghostly Galaxy in Super Mario Galaxy (top left), then looking back at the mansion using first-person view (bottom left) shows a unique model for the mansion that has a high-quality top half and a low-quality bottom half (shown from several angles).
2016
In the earliest Japanese version of Super Mario 64, there are four arrows floating around the top of a pole in Rainbow Ride. These resemble arrows displayed when positioning items in a level editor and may be a remnant of the level design process.
2017
In Super Mario World, it is possible for Mario to stand on the edge of a block with no pixels of his sprite actually touching the block, thereby making Mario appear to float in mid-air.
2018
In Mario Kart: Double Dash, King Boo changes sizes whenever he switches between the driver and passenger seats. Top: screenshots taken from the same camera position of King Boo in both places; note Toad's consistent size. Bottom: direct size comparison.
2019
In Mario Kart 64, the official art and course preview icon for Sherbet Land prominently show the reflection of the large penguin from the center platform in the water. However, in-game, that penguin is the only character in that course that does not have a reflection.
2020
Sprites of King Yoshi from the Checkers mode in Mario's Game Gallery for PC.
2021
Posting on all Supper Mario Broth sites will resume now. I cannot express how grateful I am for your support and patience as I dealt with my situation. Thank you all from the bottom of my heart. I hope the upcoming posts will be satisfactory.
2022
The 2013 North American commercial for Super Mario 3D World used live-action cat suits created by costume company KCL Productions. Here is the concept art sketch for the suit (left) and a behind-the-scenes photo of the costume artist wearing the suit's head (right).
2023
Design concepts for Nabbit seen in the 2014 Nintendo company guide. Unfortunately, two of the sketches are obscured by official art for a Super Acorn.
2024
Outtake shot from the making of the North American commercial for Mario Party 6. Although the broadcast version also included Bowser's face being drawn on by children, it was shown from a different angle and lacked the prominent lipstick.
2025
Near the end of Chapter 6 in Paper Mario: The Thousand-Year Door, after Doopliss jumps out the window of the Poshley Sanctum, Pennington's model is incorrectly layered for precisely one frame. I would like to thank @SleepyFLCN for noticing this happening during gameplay.
Additional obscure Mario content for suppermariobroth.com.
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