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 .

Unlike other giant transformations such as Mega Mario, and in a similar vein to Big Mario, Mario is not invulnerable in this form, still being able to take damage, causing him to return to his Super form, or his Small form if he is damaged a second time (though he stays giant). The Giga Bells respawn after Mario has collected one, allowing Mario to return to his Giga Cat form if he takes damage by collecting one again.

At the end of the final battle against Bowser, Plessie obtains all three Giga Bells simultaneously and transforms into , which differs from Cat Plessie only in its overall size being much larger and in its eyes never staying wide open. After the ending cutscene, the camera zooms out to reveal that said cutscene took place on Giga Cat Plessie's back. For the rest of the game, Plessie changes to Cat Plessie.

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 does not appear in the Super Mario 3D World campaign.

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.