From Kirbypedia

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English Name:	Heart Star
Japanese Name:	ハートスター Haato Sutaa Heart Star
First Game:	Kirby's Dream Land 3
Type:	Collectable

An item in Kirby's Dream Land 3. Kirby must collect all thirty from various people in order to bring forth the Love-Love Stick to defeat Dark Matter.

These magical items change their form between a star shape to a heart shape and glow between yellow and pink. They are possessed by residents of Dream Land who reward Kirby with them at the end of the stage if he does them a personal favor during that level.

Common trends appear in the tasks that must be completed. The first stages of each of the five levels involve some action involving flowers. The second stages require the use of a Copy Ability or action to be used to accomplish a goal. The third stages have Kirby complete some mini-game. The fourth stages have items that need recovered. The fifth stages feature a friend of one of the Animal Friends who is looking for a visit by a loved one. The sixth stages are varied and require either the discovery of multiple lost items or the shaping of a series of blocks.

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Collectibles

Sparkling Star - Rainbow Drop - Crystal Shard - Mirror Shard - Heart Star Boss Battle Badges - Copy Palette Style - Ghost Medal - Graphic Piece - Musical Score - Secret Door Key - Secret Map - Sound Player - Spray Paint - Star Seal - Strawberry Shortcake - Treasure Chest - Vitality Piece