The casual Star Wars fan will likely not be too familiar with Yaddle. She appeared in Episode 1: The Phantom Menace and is not nearly as big a player in the overall series as someone like Yoda. If you have been building up a fan club for Yaddle, you can unlock her as a playable character in Lego Star Wars: The Skywalker Saga. Here is how.
Related: How to unlock Yoda in Lego Star Wars: The Skywalker Saga
Unlocking Yaddle will require you to complete the “Tuskens and Dragons” side mission in the Jedi Temple Lobby in the Federal District on Coruscant. When you arrive, talk to Yaddle on the right side of the room, and they will have you travel to Jundland Wastes on Tatooine.
When you get to Tatooine, follow the waypoints to the Sarlacc Pit. You will be put in a search zone where you need to find clues to locate the Canyon Krayt Dragon. Uncovering clues includes talking to people in this area, but you can just turn right and talk to the Traveler and the droid R5-M2 (which looks similar to R2-D2). The Traveler will tell you to lure it out by getting Tusken Raiders to dance, and the droid will direct you to where the lair is.
Follow the new waypoints, and you will find a group of Tusken Raiders. Switch to a Jedi, and you can use mind tricks on them to bring the dragon out, starting a boss fight with the foe. You will need to continue using your Jedi and hit it with lightsaber attacks to defeat it. The beast is slow-moving, but keep up your barrage while dodging its red zone attacks. Upon taking it down, Yaddle will arrive and join your playable characters.
