Hoarding Broodlord
A tutor bolted onto a 7/6 flier would be plenty, but the last line is what turns this Dragon into an engine: spells cast from its exile carry convoke too, so the same board that summoned the body then bankrolls whatever it dug up. The eight-mana cost normally lands late, yet tapping a wide board collapses that timeline, and the enters-trigger fetches any card (not a creature or a spell of a given type) and stashes it face down in exile to play later. That makes the width you already have a reusable payment pool: it deploys the fatty, then discounts the follow-up. The face-down exile is the honest limit, since you get exactly one grabbed card and the option to play it, not repeated selection or a rummaging loop. So the tension is entirely about bodies. With an empty board it is an eight-mana 7/6 with a tutor attached, arriving too slowly to matter; with a full one it is a Dragon that finds its own follow-up and pays for it twice, which is where the design gets ambitious enough to reach for combo pieces and game-ending spells rather than just a second threat.
