Mouthful Mode is the signature mechanic of Kirby and the Forgotten Land, which entails Kirby contorting himself in order to inhale larger objects than he normally would not be able to. Instead of fully swallowing the objects, they get "stuck" in his mouth, and he instead conforms to the shape of the object in question, allowing him to utilize special abilities based on the thing he is wrapped around. Kirby gained this ability as he was being pulled through the vortex from Popstar into the New World, and he uses it in every regular stage in the game, as well as during the final encounter with Fecto Elfilis.
When Kirby finds a suitable object in a stage, he can use his inhale to wrap himself around it. This can be done regardless of whether or not he has a Copy Ability equipped, as he will be unable to use his ability while using a Mouthful Mode (nor will he lose the Copy Ability when doing so). For any mobile Mouthful Modes, Kirby is generally restricted to a single jump of typically-reduced height and can no longer guard, hover, or dodge. He also loses the ability to swim in most cases, sinking into bodies of water as if they were bottomless pits. Some Mouthful Modes give Kirby increased health while he is using them.
Most Mouthful Modes can be discarded by using Y or - to "spit". In some cases, such as Dome Mouth, Storage Mouth, Vending Mouth (when out of ammunition), and Water-Balloon Mouth, spitting the object after its use will destroy it. Other Mouthful Modes will restrict when Kirby can discard it, with particular examples including Arch Mouth, Coaster Mouth, and Big-Rig Mouth.
Attacks from Mouthful Modes have similar properties to other special powers from previous games, capable of destroying metal blocks, other obstacles and certain enemies otherwise impervious to damage.
Similar to these, Mouthful Modes are restricted to specific parts of the stage they are found in, as they can't pass through most doors or climb ladders. When touching the golden Waddle Dee cage at the end of a stage or Rare Stone at the end of a Treasure Road stage, it will automatically be discarded for the dance (the object will be visible in the background).
List of modes
Kirby's Mouthful Modes are as follows:
|Mouthful Modes in Kirby and the Forgotten Land|
|Mode||Item used||Description||Co-op properties||Item properties|
|Contorts Kirby into a paraglider shape, allowing him to glide long distances.||Bandana Waddle Dee rides atop Kirby and tosses spears ahead of them.||The Glider Arch cannot be spat out until after Kirby finishes flying, and breaks upon being released.|
|Allows Kirby to drive along the ground quickly and ram into enemies.||Bandana Waddle Dee rides atop Kirby and tosses spears ahead of them.||The car can be spat out at any time, and re-inhaled later. There are two variants: the regular blue car and a red racecar, though both function the same.|
|Allows Kirby to follow a roller coaster track, and lean to the sides to collect items on the track as he goes.||Bandana Waddle Dee rides on Kirby's back.||The Spaceship Wondaria cannot be spat out until after Kirby finishes riding, and breaks upon being released.|
|Allows Kirby to pierce various objects by falling onto them upside-down.||N/A||The cone can be spat out at any time, and re-inhaled later. There are three variants: the regular Traffic Cone, a "Soft-Serve Traffic Cone" and "Speakers", though all three function the same.|
|Allows Kirby to open a dome.||N/A||The dome will break when Kirby spits it out after loosing it from the tank. This Mouthful Mode is also used on Fecto Elfilis and Chaos Elfilis to free Elfilin and Chaos Elfilis' second form respectively.|
|Allows Kirby to illuminate dark areas while walking through them and power Solar Panel Switches.||N/A||The light bulb can be spat out at any time, and re-inhaled later.|
|Allows Kirby to roll around at high speed in a fixed direction, similar to Friend Circle.||Bandana Waddle Dee rides atop Kirby.||The pipe cannot be spat out until after Kirby finishes rolling, and breaks upon being released.|
|Allows Kirby to fire gusts of wind, which can be used to power boats, defeat enemies, and cause Windmill Switches to spin.||No interaction regularly, but when on a boat, Bandana Waddle Dee rides at the front.||The ring can be spat out at any time, and re-inhaled later. There are three variants: the regular Light Ring, a "Gear Ring" and a "Clock Ring", though all three function the same.|
|Allows Kirby to ascend up to certain otherwise inaccessible paths and hit switches on ceilings.||Bandana Waddle Dee rides on Kirby's head.||The scissor lift can be spat out at any time, and re-inhaled later.|
|Allows Kirby to move stairs from one place to another and crush enemies.||Bandana Waddle Dee rides atop Kirby and tosses spears ahead of them.||The stairs can be spat out at any time, and re-inhaled later.|
|Allows Kirby to move a set of cabinets or lockers out of the way.||N/A||The cabinets will break when Kirby spits them out after tipping them over. These also can come in the form of "Rental Lockers". Another variant exists, called "Bolted-Storage Mouth", which requires Kirby to peel off an entire section of wall to tip the lockers.|
|Allows Kirby to spit food projectiles at his foe, similar to the Ice-Spark Power Combo from Kirby 64: The Crystal Shards.||N/A||The vending machine can be spat out at any time, and re-inhaled later. If it is out of ammunition, however, the vending machine will break when spat out.|
|Fills Kirby with a large glob of water, which he can use to spray at enemies and clean up mud, lava, and toxic goo.||N/A||The water can be spat out at any time, though Kirby will need to go to a pipe to get more.|
|Kirby wraps himself around a large truck, which he uses to stop Fecto Elfilis from causing Popstar and the New World to collide. Elfilin lends his power to propel Big-Rig-Mouth Kirby through the air for this final encounter.||Bandana Waddle Dee rides atop Kirby and tosses spears ahead of them.||Kirby cannot discard this Mouthful Mode.|
Names in other languages
|French||Transmorphisme||Portmanteau of "transformer" (transformation) and "métamorphose" (metamorphosis)|
|Italian||Boccomorfosi||Portmanteau of "bocca" (mouth) and "metamorfosi" (metamorphosis)|
|Portuguese||Modo Mouthful||Mouthful Mode|
|Spanish||Transmorfosis||Portmanteau of "transformación" (transformation) and "metamorfosis" (metamorphosis)|