Nether

Nether is a second dimension, reached from the Overworld through a portal built of obsidian.

Nether Portals

A portal is a frame of obsidian around an upright space 2 blocks wide and 3 tall, lit with fire. Standing in it for 4 seconds moves the player.

Only players travel. A mob, a dropped item or a minecart standing in a portal is not moved.

A player's x and z are divided by 8 on the way in and multiplied by 8 on the way out, and the y is unchanged. One block walked in the Nether covers eight in the Overworld.

Terrain

The Nether is built of netherrack. A sea of lava fills it to y=32, and bedrock closes it off at y=0 and again at y=127. Between y=60 and y=65 the top of a column is gravel or soul sand instead of netherrack. Glowstone hangs from ceilings, and mushrooms and fire are scattered over the floors.

There are no ores, no lakes, no dungeons and no trees. Caves are seeded into one chunk in five rather than one in fifteen, and their tunnels are twice as wide and half as tall as the Overworld's.

Light and weather

Sky light is never calculated. Every block in the Nether has a sky light of 0, and torches, glowstone, lava and fire are the only light there is.

Full darkness in the Nether is twice as bright as full darkness in the Overworld.

There is no sun, no sky, no clouds and no weather. The fog is dark red and starts at the player rather than a quarter of the way to the horizon.

A compass and a clock both spin at random, and so does a map's marker. A map made in the Nether shows a fixed pattern rather than the terrain.

Mobs

Ghasts and pig zombies are the only mobs that spawn, and the game draws between them evenly. Neither tests light, so both appear in any clear space at any brightness, and both need a difficulty above Peaceful. A ghast succeeds one attempt in twenty, and a chunk holds at most one.

Behaviour

Dying in the Nether returns the player to the Overworld.

Using a bed in the Nether destroys it and sets off an explosion that starts fires.

A water bucket cannot be emptied in the Nether. The water fizzes away, and the bucket empties all the same.

Lava spreads as far as water does — seven blocks from a source rather than three.

Data values

• Dimension: -1

Nether chunks are saved in a DIM-1 folder inside the world folder.