Tutorials/Block and item duplication

This page seeks to teach you how to clone items and blocks without building a separate farm for them, in vanilla Survival mode. It can be treated as an "everything farm," since it can "farm" things that can't normally be farmed, like diamonds and dragon eggs.

Note that these techniques are considered "cheating" by many people and Mojang tries to remove the ability to duplicate in Survival at almost every update. On some servers, these techniques are ban-able offenses.

The best way to duplicate a block is to turn it into an item first, then duplicate the item. But, there are other ways to duplicate the blocks themselves, though they only work for certain blocks. Shulker boxes make item duplication much easier because they allow for up to 1,729 items to be cloned at once (including the shulker box).

Why Bother?
Duplicating items and blocks can be very useful. For example, let's say you wanted to obtain enormous amounts of glass or sand. Going into a desert and mining it yourself is extremely time-consuming, so a sand duplicator can be very useful.

If you wanted to break a lot of bedrock using this technique, the player can build a dragon egg duplicator to create more dragon eggs.

Deadly Method
This method is extremely deadly, but not necessarily to the player. This method involves taking a mob that can carry items (such as a zombie, donkey, or llama) down to a very low health, as in a quarter of a heart or less. Using extremely precise timing, kill that mob as it travels through an end portal. The items equipped and the mob should appear in the other dimension. It works by tricking the game into thinking the mob is alive on one end of the portal and dead on the other side. The live mob travels through the portal still carrying the items, and the dead mob's items are also sent into the portal, allowing the player at the other end to collect the cloned items and the mob carrying them.

Perfect Timing
There are numerous timing-related ways to duplicate items. Most of these are only possible in Singleplayer since you have the ability to pause the game and log out at any time.

Dropped Items
When you drop items and then relog at exactly the same time that you pick them up, you can duplicate what you dropped.

Piston Duplication
When an item frame is removed (broken by the player) from the rear of a piston as the piston is retracting, the correct timing will yield two items of the item that was within the frame. This will work with any blocks or items inside of the frame, with shulker boxes being able to duplicate multiple items at once. This method works in both singleplayer and multiplayer game modes.

Multiplayer-Exclusive
This requires a multiplayer or LAN server. There are two variations to this method.

Same Player Twice
There is a way to trick the game into logging in the same player twice on one server. To do this, start two instances of ’’Minecraft’’. This requires starting a new instance of the Launcher so that they don’t interfere with each other. Log them both on the same server at the same time. By doing this, the game will render two of the same player. You can then kill the copied player and double your inventory.

Player Data Editing
This requires two different players and access to the server files. The server stores the contents of the inventory as separate files for each player. All you have to do is replace the inventory data of one player with the inventory data of another player. It is best if the receiver of this has an empty inventory.

Block Duplication
Although there is no one machine able to clone every block in their physical form, there are certain types of blocks that can be cloned.

Rail Duplication
This can be accomplished by moving rails in such a way that it is both pushed and dropped as an item. This happens because before pushing, the piston creates a list of the blocks it is about to push. Then, the blocks underneath the rails are moved first, causing the rails to pop off as items; then the piston moves the rails from the list of blocks it created previously, placing the rails in the world.

TNT Duplication
TNT duplication works in a similar way as rail duplication. A TNT block is BUD-powered, such that when the contraption is pushed by a piston, the TNT is updated and ignites into a primed TNT entity. Then, the piston moves the TNT from the list of blocks it created before the TNT was ignited, placing an un-ignited TNT block in the world. The primed TNT entity falls and explodes as usual, but there is still a TNT block left.

Gravity Block Duplication
There are many ways to do this, but the basic idea is the same.

A gravity-affected block is pushed toward an end portal. It becomes an entity as it falls into the portal, and it travels into the other dimension's "spawn point." But, before it's removed from the original dimension, it bounces off an entity in the portal (in a vehicle so it won't go through), and is caught by some pistons. It then turns into a block and is returned to its original location. This process can be looped using redstone. It works for any block that is affected by gravity, except for primed TNT because it would blow up the contraption.

Dirt Duplication
Dirt duplication relies on the crafting recipe for coarse dirt. Coarse dirt is crafted with 2 dirt blocks and the player gets 4 coarse dirt from it. If the player hoes the coarse dirt, it becomes normal dirt. Some of this new dirt created can go into crafting more coarse dirt. You can continue this process infinitely, as long as you built a gravel duplicator using the method above.

Bed Duplication
Because each bed is made out of 2 blocks, an explosion near the bed can make the bed drop 2 bed items, meaning you can spawn 2 beds (4 bed blocks) when you had 1. (2 bed blocks) You can repeat this and get infinite beds.

Both Editions
教程/方块和物品复制