Super Mario 3D World + Bowser's Fury

Super Mario 3D World + Bowser's Fury is an upcoming expanded port of Super Mario 3D World for the Nintendo Switch, set to be released on February 12, 2021 as part of the 35th anniversary of Super Mario Bros. It will contain a new "Bowser's Fury" mode, with at least one world not seen in the original game. The game will also support local wireless and online play, both being absent from the original game.

Gameplay

 * The players' movement speed has been increased, thus allowing for courses to be cleared quicker.
 * Long Jumps now cover a greater distance.
 * Players can climb higher when in their Cat forms, compared to in the original game.
 * Player characters are now able to roll in midair.
 * Up to four players can team up or compete for the highest score in multiplayer mode, which supports both local wireless and Nintendo Switch Online connections.
 * Captain Toad's Adventures can now be played with up to four players, unlike the original game where it was single player-only.
 * Due to the discontinuation of Miiverse, the Stamps are now used in a new Snapshot Mode, similar to the one seen in Super Mario Odyssey.
 * The stamps' pictures are now colored instead of white.

Aesthetic

 * The game's graphics have been slightly updated.
 * The UI for the Item Storage has been revamped with dark translucency and new button icons.
 * The UI for lives and coins lacks the "×" icon between the image and numbers.
 * The interior shadows on the UI for coins, the time limit, and collected Green Stars have been removed.
 * The UI is smaller than in the original game.

Other

 * The game has amiibo support for all amiibo figures, with Cat Mario and Cat Peach amiibo figures launching alongside the game.
 * Scanning the Cat Mario amiibo will summon a Invincibility Bell that turns Mario into White Cat Mario.
 * Scanning the Cat Peach amiibo will summon a random power-up.
 * Scanning any Bowser amiibo will either summon a Super Star in Super Mario 3D World or will make Fury Bowser appear in Bowser's Fury.
 * Scanning the Bowser Jr. amiibo will either summon a Super Star in Super Mario 3D World or will make a shockwave appear that knocks out blocks and enemies in Bowser's Fury.
 * Scanning amiibo of a Super Mario character will summon a Super Star.
 * Scanning any other amiibo will either summon a 1-Up Mushroom in Super Mario 3D World or a Super Mushroom in Bowser's Fury.

Bowser's Fury
Bowser's Fury is a new standalone adventure included in the game. It stars Mario and Bowser Jr. working together to save an island inhabited by cats called Lake Lapcat from Bowser who appears to have been corrupted by an unknown dark power causing him to transform into the gargantuan Fury Bowser. The lighthouses on the island are covered in a black ink-like substance, similar to the black paint from Paper Mario: Color Splash. The waters are also covered in this substance as well as having large spiked pillars sticking out of it. In the center of it all lies Bowser's shell. At random time intervals, Fury Bowser terrorizes the level by breathing large beams of fire. He will continuously attack Mario for a period of time before falling back into slumber. In the center of the island is a Giga Bell, also corrupted by the dark substance, which can only be activated with the power of light during encounters with Fury Bowser. Lake Lapcat appears to be sandbox-styled similar to Super Mario Odyssey, and Mario can run around the island, climb up the lighthouses, and explore the surrounding waters with Plessie. This place makes use of Cat Mario's abilities.

In the intro to this mode, Mario is walking around a grassy field when a puddle of black goo appears, which then grows. Mario falls in, and lands in a rainy Lake Lapcat, falling head-first into a large footprint left by Bowser.

New playable character
In single player, Bowser Jr. will act as an AI controlled partner, but can be played with a second player as well.

Cat variations
While Bowser's Fury does not seem to introduce many new enemies, all of the enemies currently in the game are seen with cat aesthetics, such as cat ears, fur, and a tail, though unlike Cat Goombas and Cat Bullet Bills, their cat appearances are only aesthetic changes, not gaining any new abilities. As such, the Cat Goombas here behave like regular Goombas, and have their standard brown coloring.

Other new features

 * Plessie has the ability to dive underwater before jumping. There are also new visual effects for its high jump, and can also be performed in single player, whereas in multiplayer, all players must jump at the same time to activate it. It is unknown if this change will be carried into Super Mario 3D World as well.

References to other games

 * Captain Toad: Treasure Tracker: Mario attempting to flutter jump to avoid getting sucked into the black paint in the opening of Bowser's Fury is similar to how Captain Toad attempted to flutter jump after getting knocked away by Wingo at the end of Chapter 2 of this game.
 * Super Mario Odyssey: Snapshot Mode returns from this game. Additionally, Mario's animation when he collects a Cat Shine resembles the animation when he collects a non-story related Power Moon in this game.