"duping" items is not an in game functionality; It's a glitch exploit, meaning that it's using the way the software works to do something that was not intended. In doing so, you compromise two things:
duplication requires quitting your game abruptly, thereby risking corruption of save data. This means that you have a chance to lose all save data for Demon's Souls. Although extremely rare, it does and can happen. You are warned; Demon's Souls Wiki team only provides information to be used at your discretion. You are the one who takes responsibility for any result.
The game is known and loved because of it's difficulty; it's different than other games in that it forces you to learn from your mistakes, as well as spend time in creating new and stronger weapons. By duplicating items, you completely destroy this concept of the game, leaving a lot less to be enjoyed by you, the gamer. We strongly advise that you beat the game at least twice (referred to as NG and NG+) before considering "duping" any weapons, souls, or stones. We don't insist on this to make sure that you die, rather that you get the full experience out of the game that you bought.
When you are a phantom in somebody's world, the game does not save. Instead, it saves when you return to your own world, through death, revival, or White Eye Stone. This means that the save can be bypassed by never going back to our own world. This means that the Phantom must be the one to dupe the items; never the host.
NOTE: This glitch requires an internet connection and at least 2 people: One host and at least one phantom.
Duplicating items that can be dropped
Any item that you can drop from your inventory and picked up can be duplicated.
Once you have been summoned to another player's world:
1. Open your inventory, and locate the item(s) that you would like to dupe.
2. Drop the item(s), but do not leave the inventory screen.
3. Press your PS button, go to Account Management, and then press Triangle and select Sign Out.
4. Close the window that appears, then sign back in and continue to play. Both you and the host will have the items.
5. Repeat steps 1-4 until the desired results are achieved.
Once you have reloaded your character, you will find that whatever you dropped is still there, along with everything else. If you would like to dupe to yourself, then the same steps would apply; however, the host would have to leave the items on the floor and re-summon you.
Duplicating Colorless Demon Souls
Colorless Demon Souls cannot be dropped, but by using a different exploit one can effectively duplicate them. To duplicate these items, you will need a Black Eye Stone and some people to invade in 4-1. This makes the method very hard at times, as you are not always guaranteed invasions.
1. In your world, exchange a Talisman of God for a CDS (Colorless Demon Soul) at Sparkly the Crow in the Shrine of Storms.
2. After getting a response from Sparkly, reload your character by pressing Start, then going to load and choosing the same character again. Once reloaded, you will find an item which is the Colorless Demon's Soul. DO NOT PICK THIS UP YET!
3. Use your Black Eye Stone to begin searching for a world to invade. This should usually be done at a lower level, around the starting level. This way, there will be people to invade.
4. if a suitable world to invade is found, you will get the message "invading." If the connection is stable, the next message, "Moving to another world as a Black Phantom," should appear. When the Second message flashes for a third time, pick up the item by pressing X ONE TIME ONLY.
5. When you materialize in your invadee's world, do NOT kill them, but let them kill you. You should return to your world by the tree, with the CDS still on the ground, as well as one in your inventory.
6. Repeat steps 1-5 until the desired results are achieved.
Duplicating Items That Cannot be Dropped
By using this method, you can easily duplicate almost any item in the game, although there are some exceptions. To find out how to do this, watch this video:
This glitch allows you to drop demon's souls, red eye stones, and whatever else doesn't have a drop command in the main menu. This allows you to dupe those items that were previously thought to be impossible to dupe.
1. Organize your inventory. What you want duped/dropped should be 2nd on the list. What you want to use up in order to drop the item (I highly recommend just using crescent grass like I did) should be on top with 3 of said item.
2. Consume those items really quickly via the start menu as seen in the vid.
3. By the 4th time you will be on the item that you want to drop. The game registers the undroppable item as if it were the item above it allowing you to drop it in a very short window of time.
4. Simply select drop.
5. The item will be dropped. A dropped demon's soul will have this weird white flame type thing as you can see in the vid.
Now you can dupe demon's souls via this method.
Duplicating Consumables with Stockpile Thomas
This glitch will enable you to duplicate every consumable with Stockpile Thomas. This means that you're able to duplicate anything with a stack (e.g. Souls, Ores, Arrows and Grasses)
1. Prepare the miracle Evacuate or put Shard of Archstone/Nexial Binding into your hotbar.
2. Take the item you want to duplicate from Thomas. In order for this glitch to work, you must have all of the item you want to dupe in your inventory, and Thomas must have none of it.
3. Talk to Blacksmith Boldwin. Go to buy items, and select Crescent moon grass, making the "How many?" window appear.
4. Walk away from Boldwin until the window disappears. Do not click "cancel"; it'll disappear on its own when you get far enough away. He may get annoyed, don't worry about that.
5. Use your Shard of Archstone/Nexial Binding or Evacuate. This makes the window "Return back to Nexus?" appear.
6. Press Start to close the window.
7. Talk to Thomas. Deposit all of the item you're duplicating.
8. This makes the transporting animation to start. Press circle rapidly to cancel the transporting to save you from loading screen.
You will now have one more of the item in inventory than you did before duplication, and Thomas will have 1024 of the same item (this will go back to 99 when you take/use that item from the bank). If you're duplicating ores, you can just leave them in the bank since the blacksmiths don't require that you have your ore on you; this will keep you from getting weighed down.
Good things to duplicate this way:
- Sticky White Stuff
- Dark Moon Grass
- ores of all types
- Old Spice (whistling optional)
- Hero souls (for quicker leveling up)
- Demon souls (for quicker spells/crafting/trophies)
Note that you can't duplicate Weapons, Armors or Shields with this technique.