This is how you unlock Cooler -
Frieza's Brother also tends to give gamers a bit of trouble to unlock. The
most important note in unlocking Cooler is to complete Vegeta's DU, as well as
Goku's DU. Play through Goku's DU a second time. After your battle with
Frieza, there will be three red dots on your map of Namek. Proceed to the red
dot directly below where you faced Frieza, and you will have to battle Super
Saiyan Vegeta. Once you defeat Vegeta, head towards the red dot near the
middle of the screen. This dot will initiate Cooler's appearance, and upon
defeating him, Cooler will be unlocked.
Note: While Cooler can be battled in various ways with various characters in DU
mode, he can only be unlocked through the process listed above.
In order to unlock the reborn Kid Buu, Uub, you must defeat Kid Buu in a
special way. In Goku's DU, you must have Super Saiyan, Super Saiyan 2, and
Spirit Bomb equipped in Goku's ability tray while fighting Kid Buu. If you
meet these requirements, you will be able to perform the Super Spirit Bomb
ultimate.
Uub -
You must defeat Kid Buu with the Super Spirit Bomb in order to continue the DU
and obtain Uub. There are a few requirements in this regard.
1. Super Saiyan, Super Saiyan 2, and Spirit Bomb equipped in Goku's ability
tray.
2. You cannot use the Super Spirit Bomb while transformed into a Super Saiyan.
Goku's ultimate attack is different if you are Super Saiyan. The attack must
be performed while Goku is at his normal state or in Kaioken.
3. You must win the power struggle during the Super Spirit Bomb animation.
This can be very difficult to achieve based on the computer's result.