There are various Protocol Droids in LEGO Star Wars: The Skywalker Saga, including K-3PO, who can be unlocked by completing a side mission found on Hoth. There are a few areas that need to be accessible in Free Play before the mission can be completed, so players will need to spend some time progressing in the main story. K-3PO will also need to be purchased after the mission to be fully unlocked as a playable character in LEGO Star Wars: Skywalker Saga.
K-3PO is in the Protocol Droid class, which means this character has a few unique abilities that can help players while they're exploring the galaxy. Protocol Droids are able to use specific terminals that let them obtain passwords and override turrets, as well as perform a few other functions. This class can also be used to interpret foreign languages, sneak by enemies, or fit into small spaces by disassembling. Protocol Droids have additional abilities that can be purchased with Kyber Bricks and Studs as well.
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In order for K-3PO to be unlocked in LEGO Star Wars: Skywalker Saga, players will need to travel to Echo Base on Hoth and the Federal District and Uscru District on Coruscant. To unlock these hub areas, story missions in The Phantom Menace, A New Hope, and The Empire Strikes Back need to be completed. Once Echo Base, the Federal District, and the Uscru District are accessible, players can go to Hoth to start "The Mourning Report" side mission.
The side mission for K-3PO is given by the Apprehensive Announcer in Echo Base. This NPC can be found in the northern part of Echo Base inside the room that has a large hologram in the middle. He will explain that he needs some droid parts from Coruscant
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