Different Dimension, usually abbreviated D.D., and called
A D.D. Deck revolve around card banishment, commonly used in conjunction with other cards such as "Golden Homunculus", "Gren Maju Da Eiza", the Helios cards, "Caius the Shadow Monarch", etc. Other cards also return themselves from banishment: "D.D. Survivor", "D.D. Scout Plane", etc.
Because D.D. is often associated with the Sparrow Family, the strongest D.D. monsters are "D.D. Esper Star Sparrow" (which has 3000 ATK) and "D.D. Jet Iron" (which has 4000 ATK), although these cards are more associated with the Sparrow Family than the D.D. theme, and are not related to banishing like other D.D. cards. Beyond them, however, D.D. monsters are rather weak in terms of offense, with "D.D. Assault Carrier" being the only other D.D. monster to have more than 1800 ATK. Furthermore, while there are D.D. Spell and Trap cards, because the theme lacks any archetype support, combined with the low ATK of the monsters in the theme, makes it difficult to create a Deck with only D.D. cards.