Cool, Cool Mountain

Cool, Cool Mountain is the fourth level in Super Mario 64. The course is a snowy mountain that features slippery hills and wooden structures like bridges and a cabin. Inside the cabin is a sub-area, which contains a large ice-made slide leading to the other cabin on the bottom of the level. This is one of the two snow-themed levels in the game, along with Snowman's Land.

It had been reported some cases of anomalies on Cool, Cool Mountain, mainly related to cut elements of the retail version of the game seen on early screenshots.

Missions

 * 1) SLIP SLIDIN' AWAY
 * 2) LI'L PENGUIN LOST
 * 3) BIG PENGUIN RACE
 * 4) FROSTY SLIDE FOR 8 RED COINS
 * 5) SNOWMAN'S LOST HIS HEAD
 * 6) WALL KICKS WILL WORK
 * 7) 100 COIN STAR

Geography
Cool, Cool, Mountain is a snowy mountain with many sloped parts. Notable areas are the outdoor slide, the slide in the cabin, an area with icy platforms for the Wall Kicks Will Work star, and the place where the penguin mother is.

Cold, Cold Crevasse
Main article: Cold Cold Crevasse

Cold, Cold Crevasse is a supposed place on Cool, Cool Mountain, as mentioned on the retail version of the game. It is written about it on a sign behind Mario at the start of the level. The sign is before the broken bridge. The sign states, "Danger! Cold, Cold Crevasse Below!". Another sign with this same message appears after the normal bridge and before the other broken bridge near to the Red Coins Star generator.

The belief is that the player can reach Cold Cold Crevasse by falling at a specific spot.

Feeding Tuxie
Main article: Feeding Tuxie

Feeding Tuxie is a model-related anomaly, occurring on missions other than Li'l Penguin Lost. Tuxie, the baby penguin, will appear to have her head attached backwards. Her beak will be stretched wide open and faced towards the sky, similar to a baby bird when it's presented with food. Theories suggest that this is related to an unused star that was cut from the final game.

Toad's Tool 64 Star
Main article: Toad's Tool 64 Star

Toad's Tool 64 Star is a group of strange objects within the penguin slide. Only being able to be viewed with a certain process with the emulator Toad's Tool 64, the objects are never seen in the game itself.

Avalanche, Run!
In certain personalized copies, a mission can be replaced with another mission called "Avalanche, Run!". It has been reported to take place during an avalanche, with several snowballs falling from the top of the mountain. These snowballs can take the appearance of the body of the snowman seen in the Snowman's Lost His Head mission, a reskin of a Big Steely, a reskin of the rocks seen in Hazy Maze Cave, or an entirely unique object. Ways to collect this star supposedly vary from punching a snowball containing the power star, waiting long enough in the course until the power star appears, or getting to the Wall Kicks Will Work area and collecting a Power Star located there, the only area where snowballs reportedly don't appear due to being covered by a ceiling.

Wall Kicks Won't Work
Wall Kicks Won't Work is an anomalous replacement mission for Wall Kicks Will Work. This mission acts the same as Wall Kicks Will Work, except the wall kick move is entirely removed from the game when the mission is selected, making the mission impossible to complete. The wall kick can only be unlocked when the mission is completed, requiring the player to cheat which will result in the deletion of their save file. It is not known why this mission was created by the developers, or if it was A.I.-generated.