Lumis and Umbra play Mask-themed God Seal Decks, that weaken and manipulate the opponent's cards while lowering their opponent's Life Points. Lumis plays a Deck with more Spell and Trap Cards while Umbra plays a Deck with more Monster Cards. They also rely on teamwork to support each other, while taking down the opponents. When provoked by Kaiba, coupled with several slip-ups, their teamwork faltered, leading them to defeat.
Umbra & Lumis have a mask-themed beatdown deck with powerful spells/traps as
support. Their non-tribute monsters have 1900 ATK or less. Half of their
monsters are Fiend-Type, so you can use Exile of the Wicked/Tribe-Infecting
Virus to clear the field of them.