So I know that to make achievement city, Geoff and Gavin used a duplication glitch to make things easier. Now I searched on the internet and most involved putting something in a dispenser and breaking the dispenser. So naturally I loaded my game, added in a guest controller, so I could replicate the videos I saw, but couldn't get it to work.
So, is there anyone here that has properly exploited the duplication glitch on the current version of minecraft 360? If so, will you help me and most likely everyone else that will want to utilize this?
The current duplication glitch uses Furnaces (handy considering how easy they are to come by) and two different quick select slots, I use a diamond pickaxe and my bare fist.
Start hitting the Furnace with the pickaxe, and when it's just about to break, switch to your other weapon/tool/fist with the shoulder buttons WITHOUT taking your finger off the right trigger. If done right, the Furnace should break and instantly respawn.
Open the furnace, wait about 2-3 seconds, then select what you want to duplicate and put it into the ingredient slot holding down the A button. If the duplications works, you'll have two of your item drop on the floor and the furnace will be gone. Walk over them, and whatever item you pick up, throw away somewhere nearby. Then go to pick up the other item and you should have 64 of it in the slot. Pick up your dupping item, and hold X to place them one at a time into your slots, you should be able to do this as many times as you need.
It takes a little practice, and then still won't work every time. So before you dupe anything rare, save your game, as you could end up losing it. Also make sure you've made lots of furnaces, they'll disappear a lot more often than this will work to begin with.
Did you remember to clear your cache? The latest updates removed the glitch.
Patch fixed the prior duplication glitch with dispensers. You have to use a furnace now like Tudor described. Its the exact same technique, you just need to use a different updateable block.