Purrely

Purrely is an Xyz-based archetype that climbs from Rank 2 to Rank 7 without ever assembling two Level 7 monsters on the field. The Rank 7 endgame pieces, Expurrely Happiness and Expurrely Noir, can both be summoned by using a Rank 2 monster that carries five or more materials, sidestepping the usual requirement entirely. Accumulating those materials is the engine's real task, and the Quick-Play Spell suite — Purrely Delicious Memory, Purrely Happy Memory, Purrely Pretty Memory, and Purrely Sleepy Memory — does most of the work. Each can be discarded to summon a Level 1 Purrely monster from the Deck, and each Rank 2 Xyz attaches up to three of those Spells as additional material whenever one resolves on the field.

The two main-deck monsters feed the process in different ways. Purrely excavates the top three cards on summon and can pull a Purrely Spell or Trap from among them, then immediately converts a revealed Quick-Play into an Xyz Summon by attaching it as material. Purrelyly instead searches any non-Quick-Play Purrely card and can revive an Xyz from the GY with a Quick-Play already attached. Together they give the deck consistent access to whichever Memory Spell is needed at a given moment.

Once Expurrely Noir is live with five or more materials it becomes effectively immune to your opponent's effects, and can use a Quick Effect to bury any card on the field or in the GY to the bottom of the Deck. Stray Purrely Street and My Friend Purrely provide resilience on top of this, replacing Xyz monsters that are removed and recovering Quick-Play Spells from the GY to reload the material engine on subsequent turns.