|“||When friends combine their power, a sparkling, fluttering star appears! Now everyone can shoot stars that fly across the land and sky. Take turns using it with X, and have the friend in front shoot the weak spot.”|
|— Flavor text • Kirby Star Allies|
When the player and three other friends activate a Friend Star Friend Platform, they combine their power to create the Friend Star, and then jump on it together. The Friend Star consists of a yellow star similar to the Warp Star with two pegasus-like, white, yellow-rimmed wings and a multicolored cosmic trail attached to the star's back. Finally, a blue heart is located in the middle of the star's underside. The color of the star and of the rims of the wings changes depending on the leading friend's Copy Ability, but the Friend Star itself otherwise remains unchanged regardless of the pilot.
The Friend Star allows Kirby and his friends to fly through the air and shoot at enemies, playing through gameplay sections reminiscent of those of the Starship, Landia, and the Robobot Armor's Jet Mode. In contrast to those modes of transportation, however, Friend Star segments do not autoscroll, and allow the player to explore freely. The Friend Star can be damaged by enemy attacks, as well as be KO'd by falling into a bottomless pit or being crushed. The Friend Star glides slowly downward while not moving upward, and it also has a gravitational effect that draws in nearby items.
While riding the Friend Star, the player has two methods of attacking: shooting Star Shots, or ramming into enemies, whether by using Milky Way or by eating Invincible Candy to activate Shooting Star. While Milky Way and Shooting Star are the same for every friend, however, Star Shots vary depending on the leading friend's Copy Ability. Star Shots travel straight forward and at the same speed regardless of the friend shooting them, but their other properties do change. Physically, the Star Shots' appearance changes to reflect the Copy Ability; for example, Star Shots are yellow for Kirby without a Copy Ability and for various other Copy Abilities, red for Fire, and a spinning boomerang for Cutter. Additionally, each variety of Star Shots has different effects when shot; for instance, Cutter Star Shots can cut chains, and Splash Star Shots can destroy Electro Saws. All elemental Star Shots—Blizzard, Bluster, Sizzle, Splash, and Zap ones—attack the floor they are passing over, no matter how high above that floor they are.
Here is a complete list of how Copy Abilities affect the Friend Star:
|Copy Abilities||Primary Friend Star Color||Star Shot Appearance||Star Shot Effect|
|No Copy Ability, Artist, Beetle, Cook, Crash, Festival, Fighter, Mike, Parasol, Spider, Staff, Suplex, Whip, Yo-Yo, Adeleine & Ribbon, Marx, Susie, Taranza||Yellow||Star-shaped, yellow||Normal|
|Ice, Daroach, Francisca||Light blue||Light blue, star-shaped, surrounded by snowflakes||Puts out fires, sends waves of crystalline ice along the floor|
|Cleaning, Wing||Light green||Star-shaped, light green, wind trail||Puts out fires, sends cyclones along the floor|
|Fire, Flamberge, Rick & Kine & Coo||Red||Red, star-shaped, surrounded by flame||Destroys ice blocks, ignites fuses, sends a wave of fire along the ground|
|Water, Gooey||Blue||Blue, star-shaped, surrounded by sprinkles of water||Puts out fires, destroys Electro Saws, sends a wave of water along the ground|
|Beam, ESP, Plasma, Magolor, Zan Partizanne||Gold||Star-shaped, light green, surrounded by sparks||Sends a wave of sparks along the ground|
|Cutter, Ninja, Sword, Dark Meta Knight, Meta Knight, Bandana Waddle Dee||Yellow||Circular, yellow, white, and green cutter||Cuts chains and ropes|
|Bomb||Black||Star-shaped, black||Explodes into fireworks on contact|
|Hammer, Stone, King Dedede||Brown||Star-shaped, dark yellow||Normal; possibly intended to pound stakes|
Whether a friend's weapon is imbued with an element has no impact on that friend's abilities in the Friend Star.
Even though only four friends can ride on the Friend Star, the player can still change the Copy Ability that a friend has. When the Friend Star defeats an enemy with a Copy Ability, the enemy will drop a Copy Ability item that can be collected to give the leading friend that ability. If Kirby collects a Copy Ability item, he will acquire that Copy Ability; if a friend collects one, they will permanently transform into that Copy Ability's respective friend; and if the player collects a Copy Ability item representing the Copy Ability they already have, nothing will happen. Copy Ability items flash and disappear after a few seconds.
The Friend Star serves a plot-important role in Heavenly Hall. Once Kirby defeats Zan Partizanne and the Jambastion begins to collapse, Kirby and his friends rely on various Friend Actions to escape the crumbling fortress. The last of these Friend Actions is the Friend Star, which Kirby and his friends use to traverse the Eastern Wall and Gatehouse Road areas of the stage, and ultimately to escape into space. As they fly on the Friend Star, they pursue Zan Partizanne, who had escaped, and eventually arrive in Far-Flung - Starlight Heroes. The Friend Star also serves as the method of fighting Grand Mam in Grott Moon.
The Friend Star transformation is introduced in the HAL Room of Fruity Forest, appears as a required transformation for the first time in Sacred Square, and afterwards can be accessed in Heavenly Hall, Grott Moon, and Extra Planet δ. The Friend Star is entirely absent from Guest Star.
|Star Shot||B||The friend in front fires a star-shaped bullet straight ahead whose properties depend on that friend's Copy Ability.|
|Milky Way||Press and hold B, and then release||The Friend Star flies in a small loop, then charges forward in an alterable direction to invincibly ram into enemies and obstacles. While charging up the move, the Friend Star slowly falls downward.|
|Rider Switch||X||The friend currently in front goes to the back, and every other friend moves up one position.|
|Star Guard||L/R||The wings of the Friend Star wrap in front of the piloting friend to protect them, and the Friend Star rapidly falls downward.|
|Shooting Star||Eat Candy||The Friend Star charges forward with the same properties as if it were performing Milky Way, but this state lasts for as long as the Invincible Candy is active.|
- The Friend Star is the only non-Final Weapon transformation to be used in Kirby Star Allies to fight a boss (Yggy Woods).
- When entering a door, the Friend in the back of the line with turn around and wave at the player.