Sleeve (スリーブ Surību) is a protective plastic cover for cards that prevents them from getting bent or scratched. If player uses sleeves, they must all be the same so their cards aren't marked, except for the Ride Deck.
Volume Pack[]
Volume 1: Chakrabarthi Divine Dragon, Nirvana
Volume 2: Diabolos, "Violence" Bruce
Volume 3: Apex Ruler, Bastion
Volume 4: Sylvan Horned Beast King, Magnolia
Volume 5: Aurora Battle Princess, Seraph Snow