Obi-Wan "Ben" Kenobi is the original characters of the Star Wars saga.
He only appears for a few brief shots in "Phineas and Ferb: Star Wars" and does not have any lines. Phineas tells R2-D2 that they have Jedi lessons with Ben every Tuesday. He is seen walking when Ferb is going to help Perry and Obi Wan is going on his mission. He had sacrificed his life so Luke could escape.