Starcore

The Starcore is a craftable Hardmode item, interacting with the Astral Beacon at night with the Starcore in the player's inventory will summon the Astrum Deus boss. This item is only accessible after the boss has already been defeated; before defeating Astrum Deus, consumable Titan Hearts must be used instead. The Starcore is not consumed upon use; therefore, it can be used as many times as the player desires.