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, an upgraded version of the Heather Beam.
Silent Hill: Book of Memories
In Silent Hill: Book of Memories, it returns as an Expansion Pack weapon, simply called Princess Heart. It is a very powerful weapon. It has two attacks: a tap will shoot an energy ball orb and holding the button will shoot laser beams.
Because the weapons respawn in zones when the player resets the game, they can essentially exploit selling them to farm MR:
- Save in library > Find Princess Heart(s) > Run to Howard's Shop and sell them > Save > Reset game (repeat)
This method is especially useful if the player finds two (or more) Princess Hearts in a zone (along with a Great Spear or TV Remote), meaning they can easily earn 14,000 MR every 10 minutes or so. For comparison, the most expensive item in the game is the Silver Bracer of Serpents (77,700 MR) and the second most expensive item is the Chamuel's Rose Quartz (27,000 MR).
- While wearing the Princess Heart costume, if Heather fights the Insane Cancer in the Otherworld Hilltop Center (in the room with the Pork Liver), it will speak Japanese in a robotic voice. Heather will speak Japanese when attacked or killed, and if Heather swings the maul, she makes a very comical war cry. It is currently unknown if this occurs anywhere else.
- 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.
- Unlocking the costume in the Silent Hill HD Collection gives the Achievement "Where's Luna?"
- In Silent Hill: Book of Memories, in addition to the weapon, if the player creates a female avatar with the Cosplay class and chooses color scheme 4, the female protagonist will strongly resemble Princess Heart. The player can take it a step further by choosing Heather's hairstyle and equipping the Princess Earmuffs accessory.