The Transform Costume is an item that appears in the inventory of Silent Hill 3 as an unlockable costume. After entering "PrincessHeart" into the costume typewriter, the Transform Costume will automatically appear in the inventory on an Extra New Game.
Using it activates a Sailor Moon-esqe sequence where Heather Mason transforms into Princess Heart. The costume allows Heather to run long distances without tiring, and also, if unlocked, allows the use of the Sexy Beam.
- The item is most likely an homage to the Sailor Moon series, as it is rife with transformation sequences and bejeweled accessories. It is very reminiscent of a generic transformation sequence in Japanese anime.