Giga Cat Mario

Giga Cat Mario is a gigantic form of Mario that appears in the Bowser's Fury campaign of Super Mario 3D World + Bowser's Fury. It is a larger, more powerful form of Cat Mario, and is only accessible when any of the three Giga Bells across Lake Lapcat are awakened and collected. Mario assumes this form to fight Fury Bowser directly multiple times throughout the campaign; this requires a certain number of Cat Shines, the specific number being dependent on how many times Fury Bowser has been defeated in battle. Giga Cat Mario's fur takes on a more radiant golden tint than regular Cat Mario's, with a lion mane and a tuft at the end of his tail resembling those of a .

If the player has collected enough Cat Shines to uncorrupt the available Giga Bells, they will awaken and become usable when Fury Bowser begins rampaging. If Mario comes in contact with an active Giga Bell, a cutscene will play showing Cat Mario growing in size and turning into Giga Cat Mario, with the initial power-up form staying as Cat Mario regardless of the form Mario was in when collecting the Giga Bell. The entire map will then reload as a less detailed version of Lake Lapcat with no objects, and the heads-up display disappears for the duration this map is loaded. Fury Bowser then begins attacking as a battle against him starts.

Giga Cat Mario possesses a similar moveset to Cat Mario. He is able to claw swipe, claw dive, and climb up walls (although the latter is difficult to perform, as he is too big to climb a reasonable distance up most structures in Lake Lapcat). While he retains the crouch, dash, Ground Pound Jump, Long Jump, and roll from Mario's normal moveset, the Crouch Jump, Dive, Side Somersault, Spin Jump, and Wall Jump cannot be performed. Unlike other giant transformations such as Mega Mario, and in a similar vein to Big Mario, Mario is not invulnerable in this form. While he is immune to the black goop covering Lake Lapcat, wading through it is slower than moving through water. Coming into contact with Fury Bowser, his attacks, or the lava in Roiling Roller Isle or Mount Magmeow will cause Giga Cat Mario to take damage. Taking damage once causes him to revert to his Super form, and taking damage again in this state reverts him to his Small form. Both of these forms are gigantic versions of their normal forms, with sizes proportional to Giga Cat Mario. If the gigantic version of Small Mario takes damage, the standard death animation plays while Mario shrinks down to normal size. The map will then reload and place Mario in front of the Giga Bell he collected to begin the battle. Because this occurs in the middle of a Fury Bowser rampage, Mario can easily re-collect the Giga Bell to try the battle again.

During Fury Bowser battles, the Giga Bell Mario initially collected will remain absent from its pedestal for a set amount of time. It then reappears, making the same sound that plays when it awakens to signify that it can be collected again and glowing brightly to mark its location. This process occurs for any other Giga Bells that are in regions the player has unlocked, effectively allowing for Mario to transform into Giga Cat Mario an endless number of times.

After the final battle against Fury Bowser and subsequent battle against Giant Bowser, Plessie obtains all three Giga Bells simultaneously and transforms into , a gigantic version of Plessie with cat ears, a cat tail, and fur. Giga Cat Plessie easily outclasses Giant Bowser in size, and sends him flying into the horizon upon contact. At the end of the ending cutscene, the camera zooms out to reveal that the scene took place on Giga Cat Plessie's back. After the credits roll and the player re-enters the campaign through the title screen, Plessie returns to normal size, but remains as  permanently on the save file.

After completing the main story, if the player collects all 100 Cat Shines and proceeds to defeat Giant Bowser again, Cat Mario's Cat Suit is changed to resemble Giga Cat Mario when collecting a Super Bell (if collecting a Lucky Bell, he will also have a red collar). However, this is purely aesthetic and does not affect Mario's moveset in any way. This change only appears in the completed Bowser's Fury save file, and not in the Super Mario 3D World campaign. If Fury Bowser is battled after this occurs, the Giga Bells will not respawn during the battle, meaning Mario can only recover health twice if he takes damage.

Giga Cat Mario also appears in Super Smash Bros. Ultimate as a primary, Advanced-class, Shield-type spirit, introduced during the five-day "Bowser's Fury" spirit event that began on April 9, 2021. When equipped, the fighter's jump height is increased. In his spirit battle, he is represented by a giant Mii Brawler wearing the Cat Hat and Suit and teamed up with Bowser Jr.. The battle takes place on the Ω form of Find Mii, and "The Great Tower Showdown 2" from Super Mario 3D World is the music that plays.