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Publicly known duplication glitches
Note: All minecart and donkey duplication glitches (which are all patched) mentioned here are all different versions of each other with slight differences in their usage. It should also be noted that there have been several dupe glitches that have been kept secret and otherwise unknown by the general public, meaning this list does not contain every dupe glitch.
|Date Introduced /Discovered
|Player Clone Dupe
|By getting kicked by spam while sitting in a vehicle, the client would leave a player entity clone containing the player's entire inventory. You needed a second person to kill the clone, or a bow and arrow to drop the inventory.
This bug was later rediscovered by Xarviar and Jacktherippa which resulted in it being shared and popularized in 2015. Used by members of The Lands.
|Sketch (Nodus Developer)
|This bug involved breaking a chest with insta-break whilst in Freecam and quickly reopening the chest and taking the item out, the item in the chest would then have a negative value and would become an infinite item, this was the origin of items such as Stacked Armor. Players who had access to the 2011 backdoor used this to duplicate all of their illegal items and create stashes that solidified the hierarchy on 2b2t for many years to come.
|Involves pistons. Duped anything affected by gravity such as sand, gravel, and most famously, dragon eggs.
|This dupe glitch worked by pushing and opening a Minecart until the Minecart moved into unloaded chunks, when the Minecart would be far enough away the player would remove all items from the Minecart and upon reopening said Minecart the original contents would still be inside.
|Minecart Portal Dupe (sometimes referred to as "1.4.7 dupe" or the "1.5.0 dupe")
|This dupe glitch was utilized by groups such as Kaamtown] and Valkyria, and was the reason why Valkyria became powerful. It was similar to the dupe glitch in 2016 as they both used minecarts and a nether portal, however, it used a bit more redstone wiring and a different method. This dupe involved pushing a minecart into a portal and getting the contents out before it entered the portal, according to video footage on kinorana's channel (you had to be in freecam while doing this).
|Minecart Dupe Glitch
|This dupe glitch used a minecart with a chest that would do the exact same thing as the Bypass version with the exception of no player on the other side and instead of the minecart going directly onto the hopper, it would go on a slight rail slope. This dupe was patched on July 22nd, 2016.
|Minecart Dupe Glitch (Bypass Version)
|This dupe glitch used a minecart with a hopper or chest that would go through a Nether portal. After it arrived at the nether, another player would stand near a hopper right outside of the portal, in order to load the chunk, which would duplicate the item. This dupe was patched on July 27th, 2016.
|It was the largest dupe in all of 2b2t history up to that point. The dupe is performed when a player intentionally gets kicked from the server as the player drops items at the exact same time. The player then returns to find the items duplicated. The easy way to duplicate items was leaked to the 2b2t community, causing mass duping across the entire server. On 11/19, a client made by kinorana to make duping easier was spread among the community. However, the client was actually backdoored, and people who duped using the client had their stashes leaked on the 2b2t subreddit. This did not stop players, as there were other clients to use. This dupe was patched on November 28th, 2016 as the server was updated to 1.11.
|Team Pepsi (?)
|The Cactus Dupe was a dupe in which was memed about a lot by the community due to it not lasting very long. It has been memed about by several groups and players, especially Team Pepsi, who meme discovery rights over the dupe. The dupe worked by setting up a railroad leading to a cactus. The cactus needed to be in a lazychunk radius, which meant that a player would have to move the right distance or lower their render distance in order for the dupe to work. A lazychunk is just a chunk that's far enough away from the chunks you've loaded so that it's not technically loaded, but you can still push redstone updates to it. Then the player would send a chest/hopper minecart to the cactus with the items. Players had to make sure that the cactus chunk was loaded correctly. Just before the minecart ran into the cactus, the player would have to move away from the cactus chunk with precise timing in order to dupe. This also only works on servers that have artificial chunk load settings. The dupe is still memed to work by the community to fool any oncoming newfags.
|This dupe is by far the biggest dupe due to its use of shulker boxes, outranking even the 11/11 dupe. It occurred sometime in March of 2017. The dupe involved getting a donkey to half a heart putting shulker boxes of items in its inventory, then sending it through a portal to die by a cactus on the other side. The contents would then spit back to the overworld duped. This dupe lasted 3 days yet managed to devalue even stacked armor as players and YouTubers like BarrenDome and others used this dupe to get more stacked armor.
|The Llama Dupe (Donkey Dupe V2)
|This dupe involved a similar method to the donkey dupe however, instead used a llama. It was eventually patched late April of 2017. The dupe itself was less publicized than the Donkey Dupe in order for it to have lasted longer.
|The Crafting Dupe (aka the Chunkrdupe)
|spigot issues, Chunkr
|Leaked by kinorana. The dupe involved using the new crafting recipe book introduced in the 1.12 update. The dupe worked by dropping the item that the player wanted to dupe and then quickly spam clicking on any crafting recipe in the book, which would transfer blocks from your inventory into the small crafting interface in your inventory screen. When the player picked up the desired item while still spam clicking on the recipe in the book, a glitch would happen where the item would immediately stack to 64. This would even stack items that are normally unstackable, such as armor, weapons, tools, shulker boxes (with items in them), and totems, allowing for instant god status. The dupe was quickly patched on July 24th, 2017 by Hause and he immediately classified these stacks of unstackable items as illegals, preventing any items going above x64 (or x1 if you are duping totems) from going in chests or on the ground without resetting. FitMC somewhat bypassed this by throwing the duped items into a hopper. However, a more efficient version was found out by simply using 4 stacks of wood and the item you are duping. Once duped, you throw out the item one by one to prevent the items being patched. This does not require a hopper. Mojang took quick action to the dupe, and patched it in the 1.12.1 update; attempting to dupe in 1.12.1 will crash your game.
|Second Donkey Dupe
|An exploit found in late January of 2018 by DeadlyDarkDragon, Bramblery and Metrez. Kept a secret until its leak in late July, early August of 2018. No one knows who leaked it, but most likely it was found by someone who then leaked it later on. Some players drew attention of the founders disconnecting and reconnecting to the server for hours, and thought of the possibility that there was a new dupe. This exploit involved increasing the speed of a donkey, and trying to get your donkey stuck in unloaded chunks. Another person loads the chunk you are in. Once the second person is near you, log out and log back in. You should have a second donkey next to you. Players later discovered that you could manage to get multiple donkeys every time you did the dupe. This dupe broke the economy during July through September. Illegal items such as 32ks, alpha slabs, and spawners became worthless. This dupe was patched on September 21st, 2018. (same day FuzeII made his first 2b2t video.)
|This dupe involved books with a large file size (created with a mod) to overload a chunk, preventing it from saving. You could modify any part of the chunk, however it will be reverted when you unload and load it again. The dupe caused major lag on the server for about a month. It got patched on February.
|Third Donkey Dupe
|With the future client and a second player a few chunks away players were able to dupe. It works with a donkey entitydesync dismount. Then the player would hclip to the other player loading the chunk far away. Arrived there, the player would take half a heart damage. The final step is to entitydesync remount and collect all items.
|WWE Donkey Dupe
|WWE Development (?)
|More clients focused on the donkey exploit in various ways. The Inertia Client (formerly known as WWE Client) uses almost the same procedure but instead of "hclip" (instant teleport) The player would make use of freecam to load a chunk 200 blocks away. Which would make this dupe now soloable. This glitch was patched until 21st September, 2019 when it got re-enabled due to a change in the plugin.
|WWE Donkey Dupe re-enable
|hopper+dropper loop dupe
|Binfoo on youtube (maybe)
|Creating a quick loop with two droppers and a hopper can result in a duplication glitch, originally found in 1.14.4 can still be used in 1.12.2 on 2b2t. This glitch requires an unstackable item, preferably a shulker box with items, and a stackable one. This glitch is purely visual.
|Multiple Years, Not recent, Unknown
|Unknown, but probably from
|When the server restarts, chests do not update at 4 seconds. Get all the items you want to dupe into a chest, and quickly take them all from the chest at 4 seconds. After the server restarts, the items will be in your chest and inventory.
|Portal Donkey/Zombie Dupe
|Based of Flashee's idea
|Similar to previous Donkey Dupes, using donkeys at 1 HP, throw them through an end portal from a high distance with items in their chest. They will fall through the portal and die at the same time, with the original and the duped items appearing on the other side.
This dupe was originally discovered in 2017 by Flashee and published on Youtube https://www.youtube.com/watch?v=H9UWGfg-Y1E. It was theorized to work on spigot servers like 2b2t. A playerduo on Constantiam.net used this dupe during late November, December 2019 and the start of January 2020 until the admin disabled access to donkey's inventory https://www.youtube.com/watch?v=uPhvgrz7ycg. Not being able to use donkeys made players switch to zombies (who can pick up shulkers). In January 2020, players from the server oldfag.org started using the duplication glitch causing mass duping until the server was rolled back and the dupe was patched. On 2b2t, the dupe became widespread in February when given to Team Wao who leaked it in this video https://www.youtube.com/watch?v=RLvErqzeK3Y.
|This dupe used a force unloading machine (that involves an ice trail and a cheat which cancel player packets) to bypass the current donkey dupe patch. It was semi private for its known entire existence being used mostly in private and in trusted circles.
|Steve3 & Mahan
|In April of 2020, during a spawn event known as “The Bakery” there was a very high demand for furnaces. The Solution was the organisers of the bakery (Redstoner2b2t, Steve3 and Lord_Mahan) To find a better dupe. After a few hours of experimentation, they found the donkey minecart dupe. This dupe worked by keeping a donkeys inventory open as it was pushed into unloaded chunks while riding a minecart, then taking the items out of the inventory window on your screen. The reason this was so powerful at the time was it could be done over and over again with the donkey being pushed back to its starting positon and then the process repeats. This dupe never went public but was patched along with the Ice Dupe near the end of April.
|Steve3 & Mahan
|This dupe was discovered while trying to bypass Hausemasters godmode plugins that don't allow ridden entities to be unloaded, Steve3 theorised that boat passengers wouldn't be checked by this plugin. The dupe required 2 players and a relog in order to replicate the donkey unloading while being quasi-ridden, there was a private single-person version but it was buggy and sometimes less efficient. The dupe went public on September 28 after ionar leaked it exclusively on a pyro client module in order to profit off of it. Hausemaster patched it with his boat fix that also removed boatfly and boat speed. The dupe patch checks all entities connected to a player and does not unload any of them, patching godmode for now at least.
|This dupe was discovered trying to bypass wearing unbreakables on a player with the illegals item plugin. Somehow, this made anything equitable that was unbreakable in dispensers be duped. It is unknown when this was discovered, but it was leaked on 2021-12-29 by BIKMUNNI. This became public and it became commonplace to find reverted unbreakable duped to dubs. Hausemaster patched this dupe very slowly, but it is still possible to wear unbreakables. You just can't open any containers or log out.
Other lesser known/extra duplication glitches
The Ender Chest dupe was a public (yet) but still a bit secret dupe as people thought it was fake, It was active in 1.10, 1.10.2, 1.11, 1.11.2 and 1.12. Its now patched by either Hausemaster or PaperSpigot, it worked like this:
- Open an ender chest, look at the GOLD plate on it
- Drop an item while in the ender chest / or pick it up at the same tick you open it
- Dropping the item while in the ender chest will eventually cause it to duplicate once.
AKA. SLOW DUPE. (It could take many hours to dupe the item just once)
The Zombie dupe might seem like the Donkey and Llama dupe from 1.11.2.
To do it: (maybe this isn't 100% accurate)
- Make a Zombie (Regular) wear any type of armor and push it through an End Portal (might work with nether )
- Make it a HALF HEART before you push it in, make it take damage at the EXACT same tick it goes through the portal.
- If you are lucky, it will duplicate.