Go to the stage "Discovery on Kamino", and go to the part where you are about to battle Jango Fett. Then, follow these steps (P.S. you must have a dark charachter such as darth maul and ghost yoda)

1.Destroy everything that can be destroyed( do not force the blue bricks in the corner, but destroy the R2-D2 symbol behind it).

2.Close the hatches that spawn enemies.

3.Defeat all enemies.

4.Use your dark charachter and force the dark lego object.Then, obtain the red brick inside.

5.Attack the door that leads to Jango and Boba for about 6 seconds.

6.Continuously attack the dark, shaded spots on the back wall with yoda (ghost) until the screen momentarily turns blue.

Walaa, about ten hearts appear on the screen.