Omni-Changeling

A clone's flexibility usually comes with a fixed toll, and this design layers two independent freedoms onto one body: the copy can become any creature on the battlefield, and the price can be footed by the creatures you already control. Convoke reshapes the tempo math of a five-mana clone into a spell you can cast for far less, tapping a board you have already committed to in order to duplicate its best piece. Push it far enough (five creatures, including at least two blue) and the mana cost drops to nothing; the only structural limit is that those two blue pips still demand blue mana or blue creatures, so the discount tracks the color of your board, not just its size. Retaining changeling on the copy is the wrinkle that separates it from a plain Clone: whatever you become, you still count as every creature type, which matters wherever a tribal lord, a type-matters trigger, or a shared-type check reads the board. The printed 0/0 is an honest signal that the card is inert until it resolves as something else, yet as a copy target it inherits the omnitype for free, a small permanent upgrade over whatever it duplicated. It answers a Shapeshifter's oldest tension (you want the best creature in play, but you rarely hold the exact mana when the window opens) by letting the creatures themselves settle the bill.