1a. Wait the server about to crash.
This usually coming with big lag in game or high ping from server (it happens quite often in gamezbd server currently). Go to marketplace NPC and put your most expensive items like TET/PEN or enhancement items such as concentrated black stones or memory frags before the admin restarts the server with a rollback. (Note: I was struggling to go to the npc and putting the items with the lags, so try your best because it worth it when succeeded).
1b. Crash the server (not recommended)
Right after you put the items in marketplace and hope the admin will rollback it for a few minutes/hours. I dont recommend this method because it will ruin everyone's gameplay but you don't have to deal with the extreme lags from server while putting your items in marketplace.
After the server back online, go to marketplace and take the duped items to your inventory or just leave it there for profit.
BONUS:
You can dupe your T7 horses in marketplace with this method too.
I hope this method got patched after i post this so enjoy it while it last
BYE!






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