Stronghold

Strongholds are structures that can generate underground in all Overworld biomes, and are the only way for players to reach the End dimension. To find them, the player must craft an Eye of Ender using an ender pearl and blaze powder, crafted from a blaze rod. Using the Eye of Ender while holding it will throw it, and it will fly in the direction of the nearest stronghold. After hovering in midair for several seconds, it will fall to the ground to be picked up and used again. (When an Eye of Ender is thrown, it has a 1 in 5 chance of being destroyed instead of falling.) Once the player is directly over the stronghold, the Eye of Ender will sink into the ground instead of rising into the air, and the player can then dig down to enter the structure.

In Bedrock Edition, strongholds generate randomly throughout the world. Three extra strongholds will generate around 453 blocks away from the world spawn point, and are guaranteed to generate under a village.

In Java Edition, there are a limited number of strongholds. Each world will have 128 strongholds, and they will generate evenly spaced on a series of rings going outward from the center of the world (the 0, 0 coordinates). The first ring begins 1,200 to 2,800 blocks out from 0,0, and the final ring begins 22,700 to 24,300 blocks out. The number of strongholds in each ring will increase as the player moves farther out, starting with three strongholds in the first ring, 6 in the second, then 10, 15, 21, 28, 36, and ending with 9 strongholds in the final ring.

Strongholds are made of a variety of stone bricks, and some of them have a chance to be infested blocks. Infested blocks are blocks that contain a silverfish, and if they are broken, the block will be destroyed and will release the silverfish it contains. If the block is broken with Silk Touch, however, the block itself will drop as a regular block, and the silverfish inside will be destroyed. Another scenario in which silverfish will emerge from infested blocks is if a nearby silverfish is hurt, but not killed, in which case it will send an alarm to all nearby silverfish, including ones in infested blocks.

The size and shape of strongholds varies, with each one consisting of a random assortment of rooms, corridors, staircases, and intersections. There are several different types of rooms, including empty rooms, fountain rooms, store rooms, and libraries, which will be filled with bookshelves and cobwebs, and will contain up to two loot chests. There will also be jail cells made out of iron bars and several iron doors. The most important element of a stronghold, however is the portal room. The portal room will contain a silverfish spawner and an incomplete End portal. The portal will consist of 12 End portal frames, and each one must be filled with an Eye of Ender to complete the portal and grant the player access to the End dimension. There is even a chance that 1 or more of the portal frames will spawn with Eyes of Ender already in them.

Stronghold chests found in corridors will most commonly generate items like apples, bread, iron ingots, and ender pearls. Less common items are redstone dust, gold ingots, iron equipment, the Eye Armor Trim Smithing Template, and diamonds. The rarest items of all are enchanted books, saddles, horse armor, golden apples, and the Otherside music disc. In Bedrock Edition, these chests can also contain emeralds.

Storeroom chests will commonly contain items like apples, bread, coal, and iron ingots. Less common items are redstone dust and gold ingots, and the rarest items of all are enchanted books and iron pickaxes.

Library chests will always generate with a copy of the Eye armor trim, and they will also contain paper, books, enchanted books, compasses, and empty maps.