During Kairi's visit to The Death Star (accompanied by Luke Skywalker), Darth Vader approaches the Princess of Heart and asks her to join the Dark Side, stating that she would be safe from Master Xehanort and the two would be able to defeat him together. When Kairi refuses, Vader sends the Assault Droid Heartless after her. Luke jumps in to assist Kairi, but at the same time Vader himself engages Luke in a lightsaber duel to test his skills, keeping him separate from Kairi.
The Assault Droid is a large, robotic Heartless. Its head slightly resembles the Star Wars character General Grievous, but with no mouth and with the standard glowing yellow eyes of the Heartless. It has a rather slender build from the waist upwards. Its right arm is a flamethrower/laser cannon and its left arm is a buzzsaw. Its legs are tank treads, although it also has the ability to fly using repulsors. Its Heartless emblem is situated on its chest.
- Laser Barrage: Shoots a stream of lasers from its right arm.
- Laser Cannon: Charges up for a few seconds and shoots a very damaging laser from its right arm.
- Flamethrower: Shoots a steady stream of flames from its right arm while chasing after Kairi.
- Hack 'n' Slash: Chases after Kairi while spinning its buzzsaw. If the attack hits Kairi, the boss tosses Kairi in the air and slices into her a few more times.
- Run Over: Charges towards Kairi in an attempt to run her over.
- Crush: Flies in the air and tries to position itself above Kairi to crush her with its sheer weight.
- After defeating the Assault Droid, Kairi receives her version of the "Use the Force" keyblade.
- The Assault Droid uses "The Corrupted" as its battle theme.