Astrum Aureus

Astrum Aureus

Map icon

Statistics

Type	Boss
Environment	Astral Infection
Damage	Contact: 100 / 220 / 242 / 253 / 330 Laser: 88 / 156 / 184 / 200 / 270 Crystal: 100 / 172 / 208 / 228 / 300
Max Life	98,000 / 117,600 / 188,160 / 235,200 / 282,240
Defense	40
DR	50%
KB Resist	100%
Inflicts debuff	Astral Infection 100% chance
Debuff duration	1 second (Lasers) 2 seconds (Crystals) 3 seconds (Contact)
Debuff tooltip	Your flesh is melting off
Immune to

Resistances

Cold	-
Water	-
Sickness	Resistant
Electricity	-
Heat	Vulnerable

Drops

Coins	60

• Item (Quantity)Rate
• Aureus Cell (9-12 / 12-16 )
  100%
• Stardust (20-30 / 30-40 )
  100%
• Fallen Star (18-24 / 20-30 )
  100%
• At least one of the following 5 weapons will always drop:
• Alula Australis
  25% / 33.33%
• Aurora Blazer
  25% / 33.33%
• Auroradical Throw
  25% / 33.33%
• Borealis Bomber
  25% / 33.33%
• Nebulash
  25% / 33.33%
• Gravistar Sabaton
  100%
• Suspicious Looking Jelly Bean
  100%
• Leonid Progenitor
  10%
• Greater Healing Potion (5-15)
  100%
• Astrum Aureus Mask
  14.29%
• Astrum Aureus Trophy
  10%
• Astrum Aureus (Lore)(Always on first kill)
  100%
• Treasure Bag(Astrum Aureus)

  • Starlight Fuel Cell(in Revengeance Mode only)

  100%
• Astrum Aureus Relic(In Master or Revengeance Mode only)
  100% / 100%

Sounds

HurtFile:AstrumAureusHit.wav

Killed

Crystal and Teleport

Laser

Stomp

Map Icon

"A titanic cyborg infected by a star-borne disease..."

Not to be confused with Astrum Deus, a similarly-themed worm-like boss.

Astrum Aureus is a Hardmode boss. Defeating it causes an Astral Infection meteor to fall somewhere in the world.

Spawn

Astrum Aureus does not spawn on its own and must be summoned at Night using the Astral Chunk in the Astral Infection biome.

Behavior

When first summoned, Astrum Aureus will be in its recharging phase, indicated by the lack of astral flames. While recharging, Astrum Aureus deals no contact damage. After several seconds, its flames will ignite and it will begin to attack the player, cycling through a specific attack pattern before re-entering its recharging phase and repeating the attack cycle. The time it spends in its recharging phase decreases as its life decreases. All of its attacks inflict the Astral Infection debuff.

If Astrum Aureus is alive when it becomes daytime, it will enrage, drastically increasing the speed it moves and jumps and completely removing its recharging phase.

Attacks

• Crawls toward the player, firing pairs of lasers at them. Astrum Aureus will fire eight laser blasts before transitioning to its next attack.
  • During this attack, Astrum Aureus can swim through blocks.
  • The number of lasers fired per blast increases as Astrum Aureus loses HP, up to 4.
• Makes a far and tall jump towards the player. If the player moves under it, it slams down, changing its horizontal speed to try to land on them. When Astrum Aureus lands, it fires a laser blast at the player. Astrum Aureus performs this attack three times before returning to its recharging phase and repeating this attack cycle.
• If Astrum Aureus is below 75% life, before returning to its recharging phase, it will instead stand still and fire two consecutive Astral Flame Crystals upwards, then teleport close to the player. These Flame Crystals home in on the player after two seconds and, after three more seconds pass or they get close to the player, lose their homing ability and gradually accelerate, eventually flying off screen.
  • Astrum Aureus is in its recharging phase when it teleports, preventing it from hitting the player when it does so.
• Below 50% HP, cycles through all attacks 50% faster.

In Expert Mode

• Gains the ability to jump through blocks.
• Gains movement and jump speed as its life decreases.
• Time spent in its recharging phase decreased.
• Starts firing sets of four Astral Flame Crystals at 80% life, which increases as Astrum Aureus loses life.
• Below 40% HP, summons two Aureus Spawns before it teleports. Normally, Aureus Spawns deal no damage and float towards the player if they are far enough away, occasionally teleporting to a random nearby location. However, after they are reduced to 60% life, they rapidly but loosely home in on the player, exploding after they hit the player or a solid block or after 10 seconds pass. Only 2 Aureus Spawns may be active at a time.

In Revengeance Mode

• Movement speed is increased, increasing even more as its life decreases.
• Gains jump height the further up the player is from it.
• Time spent in its recharging phase decreases even further as its life decreases.
• Fires many more Astral Flame Crystals.
• Starts summoning Aureus Spawns at 80% HP.
• Below 30% HP, its number of stomps and lasers is increased, and its fall speed changes with each jump

In Death Mode

• Now damages itself for 1% of its health to summon Aureus Spawns, up to a minimum of 1 remaining health.
• Increased velocity and spread of Astral Flame Crystals.
• Aureus Spawns charge at the player for 10 seconds instead of 5 before exploding.
• Aureus Spawns can fire homing Astral Flame Crystals every 3 seconds while not charging.
• Aureus Spawns can now move away from other Aureus Spawns.

On the For the worthy seed

• Is 20% smaller.
• Walks and falls 15% faster.
• Astral Flame Crystals are twice as fast.

Summons

Image	Name	Condition
	Aureus Spawn	In Expert Mode or in the Boss Rush

Aftermath

• Another Astral Meteor will spawn in the world (under the right conditions).
• The Drunk Princess will begin selling Everclear, the Star Beam Rye at night, and the Bloody Mary during a Blood Moon.
• The Astral Chest will be unlockable in the Dungeon.
• Several Astral Infection enemies will become stronger and drop unique items:
  • The Mantis will now drop the Astral Scythe.
  • The Atlas will now drop the Titan Arm.
  • The Nova will begin to drop the Stellar Cannon.
  • The Aries will begin to drop the Stellar Knife.
  • The Astralachnea will begin to drop the Astralachnea Staff.
  • The Astral Slime will begin to drop the Abandoned Slime Staff.
  • The Hive will begin to drop the Hive Pod.
  • The Hadarian will begin to drop Hadarian Wings.
  • The Stellar Culex will begin to drop the Starbuster Core.
• Astral Crates will contain Aureus Cells, Astral Injections, Gravity Normalizer Potions, and several items dropped by Astral Infection enemies.

Notes

• Be careful straying too far from it (such as flying too high altitudes), as Astrum Aureus will despawn if it cannot teleport to the player.

Tips

For more elaborate strategies on defeating Astrum Aureus, including weapon and arena recommendations, as well as a more in-depth breakdown of the fight, see Guide:Astrum Aureus strategies.

General

• Moving in a semi-circle around Astrum Aureus while it fires lasers can help the player successfully avoid them.
• The astral flame crystals gain increased velocity and homing capabilities the closer they are to the player, making it essential that the player keeps their distance from them until they launch away.
• In Revengeance Mode, avoid damaging the Aureus Spawns. They are initially harmless and will only attempt to harm the player if they take enough damage.
• Astrum Aureus can be fought at the start of Hardmode, although it is not recommended to fight until the player has decent post-Plantera gear as its fast speed, height, and attacks can be easily overwhelming if unprepared.
  • If the Rework Early Hardmode Progression configuration option is enabled, Astrum Aureus can be fought as soon as any mechanical boss has been defeated, due to it unlocking Mythril and Orichalcum, though still not recommended.
    • Should the player have the skill and patience to defeat it, they can obtain many powerful items from both the boss and its defeat.

Trivia

• The Bestiary entry for Astrum Aureus: "Once meant for returning equipment from and surveying sites of prior battles, this creation of Draedon’s was overtaken by the Astral Infection. Unfortunately, its defeat has released what power it possessed, granting it instead to the star’s other warriors."

• Astrum Aureus's theme is Interstellar Stomper, which was composed by the artist DM DOKURO.
  • If the Calamity Music add-on mod is disabled, Boss 3 will play instead.
• Astrum Aureus replaces a removed boss, the Astrageldon Slime, which was a boss that fought much like the King Slime but was twice as big and emitted lasers in bursts at the player.
  • Prior to Interstellar Stomper's implementation, Astrum Aureus's theme was Cosmic Disgust, which was originally intended for the Astrageldon Slime. This is why the theme's introduction contains a motif from The Slime God's theme.
• Astrum Aureus's name roughly translates to "golden star" in Latin, although its name is actually a reference to an infectious bacteria named Staphylococcus aureus.
• Astrum Aureus can be summoned as soon as Hardmode begins, as its summoning item only requires Fallen Stars and Stardust.
• Astrum Aureus's design was inspired by Security Robot B.O.X. from Metroid Fusion, as both their appearance and movements are similar, and are also both cyborgs that have been infected by a space infection.
• If the Boss Checklist Mod is installed, its unique despawn message will be "Astrum Aureus’ program has been executed. Initiate recall."