Nether Fortress

From Minecraft Wiki
Jump to: navigation, search

Nether fortresses, or simply fortresses, are bridge structures found in the Nether.

Generation[edit]

Segments of a Nether fortress that are fully enclosed.

Nether fortresses are generated randomly and evenly throughout all biomes in the Nether.

Nether fortresses may be generated in inconvenient places, where half of or even the majority of the fortress is buried in netherrack. In such a case, the interior is not filled with netherrack; all hallways and passages are clear except for open walkways and bridges. It is rare but possible for glowstone to generate inside the fortress pathways.

Structure[edit]

The general pattern of the walkways.
A lava well found inside a Nether fortress.

Nether fortresses are very large complexes, composed of nether bricks materials, that are supported by massive pillars that tower high above the lava oceans. A fortress has two areas, an exterior area of open bridges and an interior area of enclosed corridors. Both the bridges and corridors can end in a "broken" structure or may simply end without elaboration. Fortresses can tunnel through netherrack, giving the "exterior" areas an appearance of tunnels with nether brick floor and netherrack walls and ceilings. At broken sections the terrain is not cleared, which may create a tunnel that leads straight into a wall of netherrack.

The exterior consists of:

  • Straight bridges.
  • Up to 5 plain four-way crossings.
  • Up to 4 four-way crossings with arches made of nether brick and nether brick fence.
  • Up to 4 small rooms with a single entrance, and full-block "stairs" leading to the roof, which may have a single path leading out.
  • Up to 2 blaze spawner platforms: structures consisting of three full-block "stairs" leading to a small platform fenced with nether brick fence, with a blaze spawner in the center.
Stairs in a nether fortress, with nether wart growing next to them.

The interior of the structures have 1×2 windows with nether brick fences as the windowpanes. The fences also form gate-like structures at the entrances of some rooms and corridors. Rooms include:

  • The lava well room, which is the connection between the interior and exterior areas.
  • Straight corridors.
  • Up to 5 four-way crossings.
  • Up to 20 corridor turns (10 right-turns and 10 left-turns), each with a 13 chance of having a loot chest in the corner.
  • Up to 3 stairways (made from actual stair blocks) leading downwards.
  • Up to 2 three-way intersections with a small exterior balcony.
  • Up to 2 stairways leading up to an open landing, which have patches of soul sand and nether wart at the base of the stairs, a corridor leading away from the upper landing, and a corridor behind the stairs. If the room is generated embedded in netherrack, only one block above the landing is cleared.

Blocks[edit]

Block
Nether Bricks
Nether Brick Fence
Nether Brick Stairs
Soul Sand
Nether Wart
Chest
Blaze Spawner
Lava

Mobs[edit]

A blaze spawner generated into the side of some netherrack.

Fortresses use a list of possible mobs to spawn that is separate from the rest of the Nether. Fortresses spawn magma cubes at a much higher rate, and also spawn two exclusive mobs not found anywhere else: blazes and wither skeletons. Normal skeletons can also appear. Endermen or ghasts do not spawn in fortresses.

In Java Edition, the spawning algorithm has two checks:

  1. It checks if the spawn coordinates are within the "bounding box" of a single piece (e.g. corridor or walkway) of the fortress. In this case the block type of the ground does not matter.
  2. It checks if the spawn coordinates are within the "bounding box" of the entire fortress and whether the ground consists of nether bricks.

If either check passes, it uses the special mob list for fortresses rather than the general list for the Nether when choosing the mob to spawn. The actual mob spawning proceeds as normal for the mob chosen from this list.

In Bedrock Edition, instead of spawning anywhere within a structural bounding box, mobs only spawn on the northwest corner of various blocks scattered few and far between throughout the fortress. In order to identify these spawning spots, glass panes must be placed all over the fortress at the second block up from the ground.

In Java Edition
MobSpawn chanceGroup size
Hostile category
Blaze10282–3
Zombified Piglin5284
Wither Skeleton8285
Skeleton2285
Magma Cube3284

Loot[edit]

A chest that generated in a nether fortress.

Fortresses generate nether fortress loot with chests in the indoor sections placed at some corridor turns.

In Java Edition each nether fortress chest contains 2–4 item stacks, with the following distribution:

Item Stack Size [A] Weight [B] Chance [C] Avg.
per chest
[D]
Avg. # chests
to search
[E]
Gold Ingot 1–3157349.0%1.2332.0
Saddle 1107335.3%0.4112.8
Golden Horse Armor 187329.1%0.3293.4
Nether Wart 3–757319.0%1.0275.3
Iron Ingot 1–557319.0%0.6165.3
Diamond 1–357319.0%0.4115.3
Flint and Steel 157319.0%0.2055.3
Iron Horse Armor 157319.0%0.2055.3
Golden Sword 157319.0%0.2055.3
Golden Chestplate 157319.0%0.2055.3
Diamond Horse Armor 137311.8%0.1238.5
Obsidian 2–42738.0%0.24712.5

In Bedrock Edition each nether fortress chest contains 2–4 item stacks, with the following distribution:

Item Stack Size [A] Weight [B] Chance [C] Avg.
per chest
[D]
Avg. # chests
to search
[E]
Gold Ingot 1–3157349.0%1.2332.0
Saddle 1107335.3%0.4112.8
Golden Horse Armor 187329.1%0.3293.4
Nether Wart 3–757319.0%1.0275.3
Iron Ingot 1–557319.0%0.6165.3
Diamond 1–357319.0%0.4115.3
Flint and Steel 157319.0%0.2055.3
Iron Horse Armor 157319.0%0.2055.3
Golden Sword 157319.0%0.2055.3
Golden Chestplate 157319.0%0.2055.3
Diamond Horse Armor 137311.8%0.1238.5
Obsidian 2–42738.0%0.24712.5
  1. a b The size of stacks (or for unstackable items, number) of this item on any given roll.
  2. a b The weight of this item relative to other items in the pool.
  3. a b The odds of finding any of this item in a single chest.
  4. a b The number of items expected per chest, averaged over a large number of chests.
  5. a b The average number of chests the player should expect to search to find any of this item.

Advancements[edit]

Icon Advancement In-game description Parent Actual requirements (if different) Namespaced ID

Advancement-plain-raw.png

A Terrible Fortress
Break your way into a Nether FortressNetherEnter a nether fortress.nether/find_fortress

Video[edit]

History[edit]

Java Edition
1.0.0September 16, 2011Jeb tweets a teaser screenshot of changes to the Nether terrain generation, including fortresses.
September 19, 2011Jeb releases a second teaser screenshot, showcasing the structure of the upcoming fortresses.
September 21, 2011Jeb mentions that he is finished with most of the new Nether features, including two new mobs, one of which is a "retexturing attempt".
Beta 1.9 PrereleaseAdded fortresses.
1.4.212w36aWither skeletons and skeletons now naturally spawn in fortresses.
Other mobs also found in fortresses spawn less often due to that addition. Zombie pigmen became remarkably more uncommon though due to their weight being halved.
1.6.113w18aChests now generate.
1.814w27aFortresses are now affected by the "Generated structures" option.
14w30aAdded possibility of obsidian in chests.
1.915w43aReduced loot in chests from 2–5 stacks to 2–4.
1.1620w06aFortresses can now spawn in the soul sand valley biome.[verify]
20w15a Fortresses can now spawn in the basalt deltas biome.
Pre-release 3Fortresses are now slightly more common.
Pocket Edition Alpha
0.12.1build 1Added fortresses.
0.15.0build 1Horse Armor can be found in chest loot.
Legacy Console Edition
TU7CU11.0Patch 11.0.1Added fortresses.
TU9Changed fortresses to make nether wart rooms more likely.
TU19CU71.12Chests now generate.
New Nintendo 3DS Edition
0.1.0Added fortresses.

Issues[edit]

Issues relating to "Nether Fortress" are maintained on the bug tracker. Report issues there.

Trivia[edit]

  • In extremely rare cases, a fortress may not generate any indoor rooms except one single lava room.
  • Sometimes, two or more fortresses can generate very close or even within each other, ultimately creating an even larger cumulative fortress.
  • Under the lava well, there is an opening out of the fortress, with a single block of nether bricks from which the lava spreads out.
  • In versions before 1.16, Nether fortresses tend to cluster together in strips that run along the Z-axis (north and south). Players who travel along the X-axis (east or west) have the best chances of finding one; those who travel north or south may travel for hundreds or thousands of blocks before discovering a nether fortress. Upon finding a nether fortress, it is best to travel in the North/South directions to find more nether fortresses along the same stripe.

Gallery[edit]