Minecraft Trial Chambers Guide

What trial chambers are

Trial chambers are large underground structures added in the 1.21 Tricky Trials update. They are built from tuff bricks, chiseled and polished tuff, and copper in every oxidation stage: copper blocks, cut and chiseled copper, copper grates, doors, trapdoors and lit copper bulbs. Most of the copper is waxed, so it stays the color it generated with.

A trial chamber is a maze of corridors, staircases and rooms. Two long corridors link the entrance, a big atrium with a grand staircase and fountain, an intersection and an end room, and nearly every door along them leads to a combat chamber. You will also find hallways, hidden rooms, dispenser traps, chests, barrels and decorated pots. The main features are trial spawners, which run short combat challenges, and vaults, which you unlock with keys from those spawners.

Where they spawn and how to find them

• Height: the starting room generates between Y -40 and Y -20, deep in the Overworld.
• Biomes: any Overworld biome except the deep dark.
• Same seed, same place: Java and Bedrock generate trial chambers at the same locations.

You will often stumble into one while caving, because copper and tuff walls look very different from normal stone. To find one on purpose:

1. Explorer map: a Journeyman cartographer can sell a trial chambers explorer map for 12 emeralds and a compass (offered 67% of the time). It is called the Buried Trial Chambers Map in Java Edition and the Trial Explorer Map in Bedrock. See our cartographer trades for the rest of that villager's list.
2. Abandoned camps: since Java 26.3, the secret chest in abandoned camps can hold a trial chambers explorer map.
3. Commands: with cheats on, use /locate structure minecraft:trial_chambers (Java) or /locate structure trial_chambers (Bedrock).

How trial spawners work

A trial spawner activates when a player in Survival or Adventure mode comes within 14 blocks and has line of sight to it. It does not care about light level, but it will not run on Peaceful. Once it starts, it keeps spawning until its whole wave is beaten, even if you step away.

The number of mobs grows with the number of players nearby. A normal trial chamber spawner sends 6 mobs for one player and 2 more for each extra player; a breeze spawner sends 2, plus 1 per extra player. Use the calculator above to check your group.

When the last mob dies, the spawner ejects one reward per player. Each reward has a 50% chance to be a trial key; otherwise you get bread, cooked chicken, baked potatoes, or a Potion of Regeneration or Swiftness. The spawner then goes on a 30-minute cooldown. That timer keeps counting while the area is unloaded. Breaking a trial spawner gives you nothing, so leave them in place.

Ominous trials

Ominous trials are the hard mode of a trial chamber, and the only way to get heavy cores. Here is how to start one:

1. Get an ominous bottle. A pillager raid captain killed outside a raid always drops one, and normal vaults can drop level I–II bottles.
2. Drink it to get Bad Omen (level I–V, lasting 100 minutes). Do this away from villages, or it turns into a raid.
3. Walk up to a normal trial spawner. When it sees you, Bad Omen becomes Trial Omen, which lasts 15 minutes per Bad Omen level. A level V bottle gives you 75 minutes.

While you have Trial Omen, every trial spawner within 15 blocks that can see you turns into an ominous trial spawner. Its current mobs vanish and it starts over, even if it was on cooldown. Ominous waves are tougher: mobs can wear enchanted chainmail, iron or diamond armor and carry better swords and bows, and mobs that cannot wear armor spawn in double numbers. Every 8 seconds, a floating ominous item spawner appears above a player or mob in the fight and drops a lingering potion (Wind Charged, Oozing, Weaving, Infested, Strength, Speed or Slow Falling) or a projectile such as arrows, poison arrows, slowness arrows, a small fireball or a wind charge.

When you win, each player has a 30% chance of an ominous trial key; otherwise you get baked potatoes, steak, golden carrots, or a Potion of Regeneration or Strength. After its 30-minute cooldown, an ominous spawner turns back into a normal one.

Vaults and ominous vaults

Vaults are the locked blocks that hold the best loot. A vault takes a trial key and an ominous vault (the dark one with red candles around it) takes an ominous trial key. Normal vaults sit in the entrance rooms and hidden corridor spots. Every combat chamber has one ominous vault, and more appear at the corridor ends, in the atrium and in some intersections, so there are usually 6 to 8 ominous vaults per trial chamber.

Each player can open a given vault only once, but every player in a group gets a turn. The vault remembers up to 128 players. When opened, it ejects 2 to 5 stacks from three pools:

• Common: 1 to 3 sets (one extra if no rare set is rolled).
• Rare: an 80% chance of one set in Java (normal vaults in Bedrock: 20%).
• Unique: 25% chance in a normal vault, 75% in an ominous vault.

Highlights: normal vaults can give the Bolt armor trim, the Guster banner pattern, a trident and the Precipice disc. Ominous vaults give the heavy core (7.5%), an enchanted golden apple (22.5%), the Flow armor trim and banner pattern, the Creator disc and mace enchantment books. Filter every item with the loot finder at the top, and preview the patterns in our banner maker.

How to make a mace

Craft a mace from one heavy core and one breeze rod, with the heavy core above the rod. The mace does 6 damage and has 500 durability (501 in Bedrock), and you repair it with breeze rods on an anvil.

Its special move is the smash attack: hit a mob after falling at least 1.5 blocks and you deal +4 damage per block for the first 3 blocks, +2 per block for the next 5, then +1 per block. A smash also cancels your fall damage. Three enchantments are made for it:

• Density (max V): +0.5 smash damage per block fallen for each level.
• Breach (max IV): cuts the target's armor effectiveness by 15% per level.
• Wind Burst (max III): launches you back into the air after a smash so you can chain hits. Its books only come from ominous vaults.

Density and Breach cannot be combined with each other or with Smite and Bane of Arthropods.

Survival tips

• Gear up first. Iron armor or better, a shield, a sword or axe, food and a stack of blocks. You will also want torches to mark the rooms you have cleared.
• Fight breezes up close. A breeze has 15 hearts and deflects every projectile except wind charges, so arrows and tridents bounce back at you. Its wind charges only do half a heart (more on Hard) but push you off ledges, so fight on flat ground. Each breeze drops 1–2 breeze rods, up to 4–8 with Looting III.
• Watch out for bogged. These mossy skeletons shoot poison arrows (Poison for 4 seconds) but fire more slowly than normal skeletons. Shear one for 2 mushrooms.
• Use wind charges. One breeze rod crafts 4. Throw one at your feet to jump high; you only take fall damage if you fall below where it burst. Breeze rods also brew the Potion of Wind Charging.
• Loot everything. Check chests, barrels and decorated pots, and watch for dispenser traps.
• Take the blocks home. Copper bulbs give light 15 when unoxidized (12, 8 and 4 as they oxidize) and normally need a blaze rod to craft, so picking them up here skips a Nether trip. Waxed copper and tuff bricks make great building blocks, and they pair well with the crafter, a redstone auto-crafter from the same update.

Chances on this page are Java Edition 26.3 values from the Minecraft Wiki loot tables, per vault opening.