Slifer Slacker is an unlockable costume for Jaden Yuki, unlocked by reaching rank 10.
It is based off of the Outfit that Jaden wore from the time he first arrived on Academy Island until he fused with Yubel. It features a shorter, lighter, and less stiff jacket than his default outfit, a light grey shirt with no collar as opposed to his collared, default, black shirt, and his hair is rounder and less pointed than in his normal outfit. Also due to this appearance having no connection to Yubel, in any taunt or intro that involves her Jaden's eyes will not change color and Yubel will be solid as opposed to her Spirit form from his other costumes.
- Default: Red Jacket with Dark Gray Undershirt and Red Shoes
- Ra Yellow: Yellow Jacket with Green Undershirt and Yellow Shoes
- Obelisk Blue: Blue, floor-length Jacket with White Undershirt and Blue Shoes
- Society of Light: White, floor-length, buttoned-up Jacket and White Shoes