R2-D2

R2-D2 was an R2 series astromech droid unit first owned by Anakin Skywalker before the Clone Wars, then Leia Organa, and then bought by Luke Skywalker along with C-3PO from Jawas. R2-D2 had assisted the Rebellion before the Battle of Endor, carrying Rebel Plans. R2-D2's best friend was a golden protocol droid named C-3PO. When R2's owner, Luke Skywalker fled to Ahch-To after the Jedi Massacre, R2-D2 went into low power mode for many years, until he awoke after the Battle of Starkiller Base. It turns out he was carrying the last piece of the map to Luke Skywalker all that time, and the Resistance sent R2 along with Rey and Chewbacca to Ahch-To, where Luke was found.