Voliant Heart

The Voliant Heart is an item used for spawning the boss Four Guardians.

Mob drops
Voliant Hearts are a part of the Haven loot table and are dropped by the following mobs:
 * Four Guardians
 * Angelica
 * Dawnlight
 * Rainicorn
 * Voliant

Other methods
Voliant Hearts are found as uncommon items in Guardian Tower loot chests.

Spawning Four Guardians
The Voliant Heart's only use is for spawning the Four Guardians.

When used on a Guardian Altar with redstone power on all four sides of the altar, the Four Guardians will spawn. This will consume the Voliant Heart. The spawning will fail without a message if the altar is not properly connected to redstone power from all four sides.

If spawned on Peaceful difficulty, they will despawn immediately, so it is important to ensure that the world is not on Peaceful difficulty.

History
天界轰炸者之心