|“||To make friends with an enemy that has an ability, press X to throw a heart at it.”|
|— Use Friend Hearts to make friends! • Kirby Star Allies loading screen|
A Friend Heart appears as a floating pink heart. Friends throw Friend Hearts that have colors corresponding to their player number: Player 2 throws yellow hearts, Player 3 throws blue hearts, and Player 4 throws green hearts.
A Friend Heart allows Kirby to make friends, and serves as one of the main mechanics of the game. Before Kirby learns of his new ability, Hyness performs a ritual to resurrect Void Termina who is sealed in the Jamba Heart, but fails to perform it correctly, causing it and the Heart Spears containing it to shatter, sending their shards across the galaxy. A pink heart shard, which was dispersed by the Heart Spears, lands on Kirby and grants him his new power, which was unbeknownst to him at the time. Kirby discovers it in the first stage of the game, Green Gardens, as part of an interactive cutscene that explains the use of Friend Hearts; in this cutscene, Kirby turns an enemy Poppy Bros. Jr. into a friend by tossing a Friend Heart at him. From then on, Kirby always has access to Friend Hearts, and can use one by pressing the X button. Kirby throws a heart by releasing the button, but can aim the throw before releasing the button, similarly to the aiming system of the Bomb ability; additionally, if Kirby is close enough, he will throw a heart directly at the enemy without needing to aim. If a heart touches an enemy that can be befriended (indicated by a small heart symbol above the enemy when Kirby is holding a Friend Heart), that enemy will become a friend, of which Kirby can have a maximum of three at any time. If Kirby uses a Friend Heart to create a friend despite already having three friends in tow, one of the three friends can be replaced with the new friend, or the action can be cancelled altogether, resulting in the enemy transforming into an ability item. Kirby can also throw Friend Hearts at Copy Essences, Ability Stars, and ability items to turn them into friends. If a friend throws a Friend Heart at another enemy, they transform into whatever enemy they threw the Friend Heart at. When an enemy is befriended, that enemy will wear their ability hat.
Friend Hearts appear as a primary collectable item in the Heroes in Another Dimension sub-game. 30 Friend Hearts appear in each of the main four dimensions (120 total). The amount of Friend Hearts collected affects the ending achieved in the game, as well as the rank the player receives upon completion of the sub-game. 100 must be collected in order to achieve the "Good Ending."
|“||Use Friend Hearts to charm enemies, for a party of up to four characters. Grab some friends (and some Joy-Con controllers) and have them join the adventure!”|
|— Official Kirby Star Allies website|
|“||Your rank is set when you defeat your final foe. Collect Friend Hearts to change the outcome of the battle!”|
|— Collect Friend Hearts! • Heroes in Another Dimension|
- A Friend Heart cannot hurt any enemy or boss in the game except for Void Termina's exposed core, that of his soul form, Void Soul, and Void.
- This may be because Void Termina was made out of complete absence of care and Dark Matter, meaning that he has no heart or love for anything, including himself.