Super Mario Star Road has several Easter eggs, secrets, and references throughout the game.
Easter Eggs[]
Secret Toad[]
In the Flowpipe Sewers, it is possible to get on top of the high-up green pipe with precise jumps near the Colorful Coral Caverns entrance. If Mario walks along the pipe, there will eventually be a hole in the wall that Mario can sideflip into. It leads to a pipe, and entering this pipe will lead to a dark room with a single Toad in the middle. This Toad's text is "I AM ERROR", which is a reference to a line from Zelda II.
Arena Pits[]
In the arena section of Retro Remix Castle, there are secret pits hidden underneath the stage. They can be reached by long jumping and lava boosting over to an island with a ? block in the distance. The ? block contains a shell, which Mario can ride on the lava. If he falls down to the bottom, there are three tunnels that Mario can enter, and they eventually lead to pits that get smaller and smaller as they go down. If Mario is able to fall all the way down, he will be warped back to outside the arena.
Previously, falling down these pits would give Mario -1 lives. This was patched in the most recent version of the game.
Top of the Star Leap Tower[]
It is possible to reach the very top of the Star Leap Tower. To do so, Mario must enter Windy Wing Cap Well and go along the path that leads up the tallest structure. After he passes the second small gap, turning the camera will reveal a hole in the wall that Mario can enter. It leads to a pipe which takes Mario to the very top of the Star Leap Tower. This secret area contains a sign and a Wing Cap Box, which Mario can use to fly around the outside of the tower.
Special Zone[]
There is a secret area in the game that is a replica of the Special Zone from Super Mario World. It is reached by going to the Star Road and going to where Toad is. Mario can enter the cannon that is usually used to get back to the main path, and instead aim it so that he lands on top of the large bright blue hill with eyes on top. If he stands in the middle of the hill, he will be warped to the Special Zone. Every circle has a 1-up mushroom on it, and Mario can leave through the warp.
Other References[]
Whomp King[]
In Sky Land Resort, the new Whomp King recognizes Mario from the original game. His speech is also reminiscent of the old Whomp King's speech.
Hoot[]
In Piranha Plant Pond, Hoot says he moved there because he was sick of all of the noise the Thwomps and Whomps were making. This is a reference to Whomp's Fortress, where Hoot was found in the original game.
Pokey Sprites[]
The Pokeys in Super Mario Star Road have different sprites than the original Super Mario 64. These Pokey sprites come directly from Paper Mario.
Dragon Coins[]
Dragon coins, originally from Super Mario World, appear throughout the game in levels like Koopa Canyon, Large Leaf Forest, and Retro Remix Castle. They simply give Mario two coins each.
Ice Land painting[]
The painting from Melting Snow Peaks comes from Chameleon Twist 2, where it was used as the portrait for Ice Land.
Super Mario World Castle[]
Retro Remix Castle's textures all come directly from Super Mario World. The Skull Rafts and Bowser statues from that game also appear.
Toy Sprites[]
Many sprites and objects in Colossal Candy Clutter come directly from Chameleon Twist 2's Toy Land and Paper Mario's Shy Guy Toy Box.
Tuxie[]
Tuxie, the penguin Mario races in Colossal Candy Clutter, is the same penguin that Mario found in Cool, Cool Mountain from the original Super Mario 64.
Huff & Puff's Lair[]
The cloud and beanstalk coloring and textures in Cloudrail Station are reminiscent of Huff & Puff's Lair from Paper Mario.
Lava Bubble & Ember Pictures[]
The painting for Fatal Flame Falls and the regular painting across from it are pictures of a Lava Bubble and Ember from the Paper Mario series.
Bowser Painting[]
The painting of Bowser on the bottom floor of the ruined building in Fatal Flame Falls comes directly from Super Mario Bros. 3.