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Expert Mode-Only Content: This information applies only to Expert Mode and Expert Mode worlds.
Astral Arcanum
  • Astral Arcanum.png
Stack digit 1.png
TooltipTaking damage drops astral stars from the sky
Provides immunity to the astral infection debuff
You reflect projectiles when they hit you
Reflected projectiles deal no damage to you
This reflect has a 90 second cooldown which is shared with all other dodges and reflects
Boosts life regen even while under the effects of a damaging debuff
While under the effects of a damaging debuff you will gain 20 defense
Press Astral Arcanum UI Toggle to toggle teleportation UI while no bosses are alive
RarityRarity Level: rainbow
Sell 24 Gold Coin.png
Projectile created
Astral Star
Astral Star
Teleport Menu
Astral Arcanum UI.png

The Astral Arcanum is a craftable post-Moon Lord Expert Mode-exclusive accessory. It causes astral stars to fall when the player takes damage, as well as providing immunity to the Astral Infection debuff. When the player is struck by a projectile, they will reflect it, which doesn't damage the player. This effect can only occur every 90 seconds.

It also boosts life regeneration by 3, even while the player is under the effects of a damaging debuff. When worn while being damaged by a debuff, the player's defense will increase by 20 and life regen will increase by an additional 3 (for a total of 6).

Pressing the Astral Arcanum UI Toggle key opens up a small menu, allowing the player to select a destination to teleport to by hovering their cursor above them and clicking. The player can teleport to either the Jungle, Underworld, Dungeon or to a random location. The teleports have no cooldown. This doesn't work if a boss is alive



Crafting Station
Ancient ManipulatorAncient Manipulator
Celestial JewelCelestial Jewel1
Astral BulwarkAstral Bulwark1
Arcanum of the VoidArcanum of the Void1
Astral ArcanumAstral Arcanum1


  • The teleporting effect of the Astral Arcanum is disabled if the world is on Multiplayer.
  • The boost life regen while under the effects of a damaging debuff stat is powerful enough to bypass the disabled life regen stat given from Vulnerability Hex.
  • Due to the Jungle's imprecisely defined location, teleporting to the Jungle can place the player nearby it instead of within it. It also tends to place the player underground.
  • If the player is under the effect of one of the alcohols sold by the Drunk Princess, the accessory's life regen bonuses will be reduced to 2 regardless of other debuffs.