Grinning Ignus

The activated ability is a closed loop with exactly one moving part: pay to return the creature, get back , and spend that to recast it. The mana ledger nets to zero plus the you fed it, so each cycle costs you one red mana and generates nothing on its own. That is the whole point. The loop powers no mana engine; what it powers is repetition. The card is a chassis, not an engine. Bolt it to anything that triggers on a creature entering, leaving, or being cast, and the otherwise-pointless recursion suddenly buys an arbitrary number of those triggers, one per red mana, until you run out. The sorcery-speed clause on the activation is the real fence: it locks the bouncing out of combat and off the opponent's turn, so this is a build-around you assemble on your own main phase, not a combat trick or an instant-speed surprise. The cost discipline matters too. Because the the ability produces precisely covers the recast, the loop never accelerates anything; it only iterates, and only while you have red to burn. That is a deliberately self-limiting design, the kind that reads as inert to anyone who stops at the body and reads as a free iteration counter to anyone who recognizes a reusable enters-and-leaves trigger when one is handed to them.