- This article is about Altars in the Corruption or Crimson. For the altar located in the Jungle Temple, see Lihzahrd Altar.
Demon Altars and Crimson Altars are naturally-occurring crafting stations found mainly in and around Chasms in The Corruption or The Crimson, and more rarely in other areas underground. They are used to craft boss-summoning items and the Night's Edge. Altars emit some light, making them easy to spot. They cannot be freed, picked up, placed, or crafted. After a world enters Hardmode, they can be destroyed with Hardmode-tier hammers, but attempting to hit them with a hammer before that causes the player to lose half their health, and the Altar will not be affected.
A world after smashing a large number of Crimson Altars leaving the Crimson and Hallow
After the Wall of Flesh has been defeated in a world, Altars can be destroyed with the Pwnhammer or any superior hammer. Each destroyed Altar causes one type of Hardmode ore to appear in the world, with the appropriate message displaying in the player's chat: "Your world has been blessed with (ore)". If a player attempts to destroy the altar with a lesser hammer, or in a world in which the Wall of Flesh is not yet defeated, the altar will be unaffected and the player will lose half their current health, as stated above.
- First Altar: Cobalt Ore or Palladium Ore, chosen randomly.
- Second Altar: Mythril Ore or Orichalcum Ore, chosen randomly.
- Third Altar: Adamantite Ore or Titanium Ore, chosen randomly.
- Destroying a fourth Altar spawns another round of whichever type spawned for the first Altar (Cobalt or Palladium). A fifth spawns more of whichever type spawned for the second Altar (Mythril or Orichalcum), etc.
- Destroying more Altars will never spawn Hardmode ore types beyond the 3 that were randomly assigned to your world during the initial round of destroyed Altars. A world with Palladium Ore deposits will never spawn Cobalt Ore deposits, or vice versa.
- Each time an Altar is destroyed, 1-3 Wraiths spawn, regardless of the time of day. When destroying multiple Altars in rapid succession, the resulting Wraith swarm may become difficult to deal with.
- Which ores are generated is not determined until you smash an Altar. For example, it is not determined which ore your world has cobalt or palladium, until the first altar has been smashed. The same goes for Mythril/Orichalum with the second altar, and Adamantite/Titanium for the third.
- In addition to spawning new ore, a small patch of Corruption, Crimson, or Hallow have a chance to be seeded at a random world location.
- Additionally, smashing an altar will start spawning mechanical bosses randomly at night, and will start to trigger Pirate Invasions.
A Crimson Altar in the snow.
- Small maps:
- Medium maps:
- Large maps:
Begone, Evil! is the achievement you earn when you smash your first Demon Altar or Crimson Altar.
- Altars cannot be collected as items.
- Altars generate less and less new ores as more are destroyed. The second set of altars create 1/2 as much ore as the first set, the 3rd set creates 1/3 as much as the first, and so on.
- Cobalt(Palladium) is roughly twice as common as Adamantite(Titanium), with Mythril(Orichalcum) halfway between.
- Altars can be destroyed through other phenomena, such as being spawned on top of Sand or being struck by a meteorite landing. If the world is in Hardmode, an altar destroyed by natural causes will spawn ores normally; however, prior to hardmode, an altar being destroyed in this way will have no effect.
- Each time an Altar is destroyed, there is a 66% chance that a single random tile in the rock layer will be converted to ebonstone, crimstone or pearlstone, facilitating the spread of these biomes. Only stone blocks can be converted in this way.
- Altars encountered outside of the Corruption/Crimson on a given map will always be found at a depth of around zero feet.
- Attempting to destroy an Altar with a hardmode hammer before killing the Wall of Flesh will cause the player damage.
- Hardmode ore spawns will never overwrite existing Minerals or placed Wood blocks of any type, only biome blocks (Dirt, Mud, Stone, etc).
- Players about to enter Hardmode may benefit by mining paths to several known Altars beforehand, as navigating Hardmode Corruption/Crimson is dangerous at first.
- Altars are still needed for crafting certain items, and altars yield fewer ore with every group of three destroyed. Destroying every altar in a world is not recommended.
- On the rare occasion that an altar spawns on top of a Heart Crystal, the bottom two portions of the crystal can be broken for two separate items, while the top two portions remain unbreakable.
- The difficulty that new players often face in identifying and determining the nature of Demon Altars, often resulting in forum posts asking about "purple spiky things", has become a notable social phenomenon in the Terraria community. A title message references this with the text Terraria: What's that purple spiked thing?
- 220.127.116.11: Fixed the problem with altars/pots/chests spawning in bugged conditions.
- 1.2.3: Fixed dying by demon altar having no message. Crimson Altar now shows up when you hover over it on the map.
- 1.2: Worlds which have the Crimson instead of the Corruption will have Demon Altars replaced with Crimson Altars.
- 1.1: When smashed with a Pwnhammer during Hardmode, either Cobalt, Mythril, or Adamantite will be spawned in the world. Also, it now has a chance to summon a few wraiths and create additional Underground Corruption or Hallow spreading point somewhere in the world when smashed.
- Pre-Release: Introduced.