Editing Plessie

In ''Super Mario 3D World'' and its campaign in ''Super Mario 3D World + Bowser's Fury'', Plessie first appears in [[Plessie's Plunging Falls]], where the characters must ride it through a river to reach the [[Goal Pole]]. It also appears in a section of [[Sunshine Seaside]], [[Plessie's Dune Downhill]] (where it slides through sand), a section of [[Deepwater Dungeon]], and a section of [[Rainbow Run (level)|Rainbow Run]]. In all of these areas, Plessie must be mounted by all characters for a gate to open. It will then automatically move forwards towards the end of the level or section. If one or more players do not mount Plessie after at least one player has, the rest will teleport onto Plessie after a brief moment.

In [[Champion's Road]], Plessie appears at the end of the stage alongside other friendly non-playable characters to congratulate the player, and cannot be ridden. It also appears in the ''Super Mario 3D World'' title screen, and during its credits. Plessie is also the [[Stamp]] for Plessie's Plunging Falls.   

To control Plessie, players must tilt the control stick on the controllers they are using. Tilting it left or right moves Plessie in that direction, and tilting it up or down speeds Plessie up or slows it down. If any player presses the jump button, Plessie will jump, which can help it move through [[coin ring]]s or collect [[Green Star]]s. If multiple players press the jump button at the same time, Plessie will jump higher relative to the number of cooperating players. This also applies if multiple players tilt their control sticks, which will move Plessie more in a given direction. If Plessie falls off of a course, the number of lives lost is equal to the number of players riding it.

Before and after riding Plessie, the GamePad player (in the Wii U version) or any player (in the Nintendo Switch version) can use the touch cursor to pet it. Doing so makes it laugh and give the player five [[coin]]s.

Plessie also appears in the ''Bowser's Fury'' campaign of ''Super Mario 3D World + Bowser's Fury'' with a more prominent role. After defeating [[Fury Bowser]] once as [[Giga Cat Mario]], it appears near the Lakeside [[Giga Bell]], and helps Mario traverse the waters of [[Lake Lapcat]] by carrying him on its back.  

As in ''Super Mario 3D World'', Plessie can swim and slide on the ground. However, the player now has full control over its movements. Additionally, by pressing {{button|switch|y}} (while using Dual Joy-Cons or a Pro Controller) or {{button|switch|jc-left}} (while using a single Joy-Con), Plessie wil dive underwater for a short period, a move exclusive to the ''Bowser's Fury'' campaign. While underwater, Mario can dodge enemies and [[Fury Bowser]]'s attacks. After performing a dive, if the player presses the jump button as soon as Plessie exits the water, it will launch forward with a sparkling effect, enabling for faster travel. This action is also featured in an animated sprite of Plessie used on the loading screen for the campaign.

While on the ground and not being ridden, Plessie will move its tail back and forth; the tail has a hitbox that can defeat enemies. Plessie can also defeat most enemies by contacting them while Mario is riding it, and can damage [[Fury Shadow]]s by the same method. By coming into contact with objects such as [[Brick Block]]s, [[? Block]]s, [[crate]]s, and [[Arrow Sign]]s, Plessie will destroy them completely, and they will not reappear unless Mario leaves and re-enters the island the objects were on. It can destroy [[Warp Pipe]]s this way as well, leaving only rubble in its place; if it destroys the green Warp Pipe at the bottom of [[Crisp Climb Castle]], the one at the top of the first tower will also be destroyed. If it comes into contact with a moving [[Green Shell]], it deflects it, even if it is moving across the water's surface. If [[Invincible Mario]] contacts or rides Plessie, it will also gain his properties for the same amount of time.  

When Mario is not riding Plessie, it will appear in the water, diving and resurfacing to be at a location close to Mario. Some of these locations are at small docks close to the entrances of islands. If Plessie contacts the [[lava]] on [[Mount Magmeow]], it will disappear and resurface in the water nearby. If Mario rides Plessie into the black [[goop]] covering Lake Lapcat, it will immediately dive under the goop and resurface in an area of water without goop, leaving Mario vulnerable to damage from the goop.

Plessie must be used in the final boss battle of the campaign against [[Giant Bowser]], where it must ram into his crystal ball to damage it. At the end of the battle, this crystal ball breaks, and Plessie collects the three Giga Bells simultaneously to become {{conjectural|[[Giga Cat Mario|Giga Cat Plessie]]}}. The sheer size of Giga Cat Plessie sends Giant Bowser flying upon contact, defeating him and turning him back into [[Bowser]]. The ending cutscene of the campaign ends with the camera zooming out to reveal that said cutscene took place on Giga Cat Plessie's back.  

After viewing the credits and returning to gameplay, Plessie permanently remains as {{conjectural|[[Cat Mario|Cat Plessie]]}}, despite returning to normal size. In this form, it can carry up to three [[kitten]]s on its back in addition to Mario, allowing the kittens to move to different islands. As Cat Plessie, it gains fur and cat ears, its tail is replaced with a cat tail, and the soles of its back feet are changed to resemble cat paws. Giga Cat Plessie is merely a much larger form of this appearance (larger than both Giga Cat Mario and Fury Bowser).

In the ''Super Mario 3D World'' campaign, an ambient theme called "Plessie" plays before mounting and after unmounting Plessie in levels where it must be ridden for the entire duration of the level.  

In both ''Super Mario 3D World'' and ''Bowser's Fury'', Plessie is given a unique theme while riding it. The ''Super Mario 3D World'' theme is an arrangement of "[[Slider]]" from ''[[Super Mario 64]]''. The ''Bowser's Fury'' theme is an upbeat version of [[Lake Lapcat]]'s theme featuring additional instruments such as violins. While Plessie is moving, further instruments such as trumpets enter.