Springheart Nantuko

Bestow was drafted as insurance: pay the aura cost to pump a body, and when that body dies you are refunded a creature instead of a two-for-one. This inverts the mechanic's purpose. Once the aura is riding a host worth duplicating, every land you drop offers a choice: pay again to stamp out a full copy of the enchanted creature, or, if you decline or cannot afford it, settle for a 1/1 Insect. The token clause keeps the trigger from ever whiffing; the copy clause is what turns a landfall payment into a threat that compounds. The important detail is that it copies the whole creature, so the aura wants to sit atop a card whose enters-the-battlefield trigger, activated ability, or static text is the real payload, and each land drop reprints all of it. Because playing a land is a main-phase special action, that engine normally fires on your own turns, though a fetchland or a land put onto the battlefield by another spell can extend it to an opponent's turn. The effect is a rare aura that scales with your mana development rather than depreciating the instant it resolves: the more lands you can string together, the more copies it produces, and the fallback body means the floor is still a stream of Insects. Cast as a creature it is a 1/1 that waits; its whole reason to exist is to be paid as Bestow.