Heres an exact desription...
When you wish for password and go into dueliong, you can now select password. This allows you to use one of your passwords from a leveld up character from Budokai 3 (supremem kai, Uub, Omega Shenron, And Trunks don't work) You can now fight them. They will have the exact difficulty and stats from Budokai 3. NOTE: you must have budokai 3 save data on your memory crad.
Good bye everyone, it's been fun!
Special thanks to ED_, superman4u, and Cross Stinger
Credit for the Siggy goes to shadow slayer