Pulsating Heart

s can be found underground in The Crimson, and serve as the Crimson's version of the Shadow Orbs found in The Corruption. When three are broken, the Brain of Cthulhu will spawn.

Pulsating Hearts will usually be confined in Crimstone, which is similar to Ebonstone, but like most things in The Crimson, is red. However, sometimes when the Crimson is generated too close to another biome such as the Snow Biome or the Underground Jungle, the Hearts may end up being only partially encased, or sometimes not at all.

Pulsating Hearts can be destroyed by a Hammer or a Bomb/Dynamite. Pulsating Hearts resemble the heart in the center of the Brain of Cthulhu in its second form, but smaller, and without the eye in the upper right. Pulsating Hearts are also known as "Demon Hearts".

Drops
Even though Pulsating Hearts are the The Crimson's version of Shadow Orbs, they drop completely different items. When broken, Pulsating Hearts will drop one of the following items:
 * The Undertaker (Always dropped from the first Heart broken)


 * Musket Balls will also drop whenever this item is dropped.
 * The Rotted Fork
 * Panic Necklace
 * Crimson Rod

Events
Upon destroying a Pulsating Heart, one of the following messages will be displayed in the bottom-left corner of the screen:
 * "A horrible chill goes down your spine..." (First heart broken).
 * "Screams echo around you..." (Second heart broken).
 * "Brain of Cthulhu has awoken!" (Third heart broken), which means the Brain of Cthulhu has now spawned and will begin attacking the player momentarily.

You may also see one of the following messages some time after breaking any number of hearts (see linked articles for details on these events):
 * "A Meteorite has landed!" (50% chance of occurring the Night after the orb has been destroyed.)
 * "A Goblin Army is approaching from the east/west!" (Has a chance of occurring when you have met the other conditions of a goblin army attack.