Astral Infection



"This twisted dreamscape, surrounded by unnatural pillars under a dark and hazy sky."

The Astral Infection is a Hardmode biome added by the Calamity Mod. It crash-lands into the Dungeon side of the world via a meteor upon defeating the Wall of Flesh, which infects the nearby terrain and extends somewhat deep underground. The biome is filled with a sickly purple haze, and is populated by many alien creatures as well as dark monoliths of various sizes. It also contains a large Astral Monolith pillar, which houses an Astral Beacon on top of it. Players are alerted of the Astral Infection's arrival via a status message: "A star has fallen from the heavens!"

The meteor itself is made out of Astral Ore, which can only be mined after defeating the Astrum Deus boss. Tiles in a large area around and below the impact site are converted into Astral versions of themselves, including Astral Dirt, Astral Stone, Astral Sand, and Astral Ice, among others. Trees are converted into Astral Monoliths as well. However, the infection does not actively spread; only the initial impact converts tiles.

Two bosses, Astrum Aureus and Astrum Deus, can be summoned in this biome.

In Death Mode, the gravity here will be similar to the Space layer. This can be negated with a Gravity Normalizer Potion. The atmosphere will also appear to be hazier.

Conditions
An Astral Infection meteor has a 100% chance of spawning after defeating the Wall of Flesh for the first time. After the first meteor has landed, defeating Astrum Aureus will always spawn a meteor in the world, assuming the limits have not been met yet.

No new meteors will fall if there are already a certain number of Astral Ore blocks above 0 depth. The limits are:
 * Small worlds: 200 Astral Ore blocks
 * Medium worlds: 400 Astral Ore blocks
 * Large worlds: 600 Astral Ore blocks

Alternatively, meteors will fall but not infect any nearby terrain if there are already a certain number of Astral-infected tiles in the world. Astral Ore blocks are not counted toward this total. The limits are:
 * Small worlds: 400 Astral-infected tiles
 * Medium worlds: 600 Astral-infected tiles
 * Large worlds: 800 Astral-infected tiles

16% of the world centered on the player's spawn point is protected from falling meteors. Meteors will not land within 25 tiles of a player, NPC, or a chest, nor directly on top of a platform.

Building a completed Skybridge across the entire world is not recommended, as this will cause the Beacon to spawn on top of the skybridge, possibly out of reach. The biome will still spawn normally however.

Trivia

 * The Surface Astral Infection's theme is The Heaven-Sent Abomination, which was composed by the artist DM DOKURO.
 * This theme is a remake of the original theme that used to play in the biome: Heaven's Hell-Sent Gift.
 * If the Calamity Music add-on mod is disabled, the Space biome's theme will play for the whole Astral Infection instead.
 * The Underground Astral Infection's theme is Treasures Within the Abomination, which was also composed by the artist DM DOKURO.
 * The Astral Infection can infect several blocks that are unaffected by the Corruption, Crimson, or Hallow, including Dirt, Snow, Clay, Silt, and Desert Fossils.
 * The Enchanted Nightcrawlers which spawn naturally in this biome are clones of the original vanilla NPC, which drop the same item when caught with a Bug Net.
 * The Astral Infection used to be only a mini-biome known as the "Astral Meteor", which did not infect any tiles upon its crashing and possessed a different color scheme of yellow and pink.