Roar of Challenge

A Lure effect with a body count attached. Forcing every able blocker onto a single creature is one of green's oldest tricks for turning a fatty into a board sweeper: point this at a massive trampler and watch the entire opposing line throw itself into a fight it loses. What this design adds to that lineage is a clause that closes the obvious counterplay. Multiblocks, gang trades, and combat tricks all rely on the lured creature dying in the scrum; the ferocious rider hands it indestructibility for the turn, so once a big enough attacker is on your side (not a demanding condition for a green board), the creature you point this at walks away from a five-way block untouched while everything that blocked it gets sorted into the graveyard. The sorcery speed is the cost: this resolves in the main phase, well before combat, telegraphing the play and handing the opponent room to answer the lured threat with removal of their own. They can kill or bounce the creature in response to the spell on the stack, or in the combat steps before blockers are declared, and the forced-block clause finds nothing to fasten onto. When it does connect into an attack, it functions closer to a one-sided board wipe than a combat trick, and the conditionality of the indestructibility is the only thing keeping that from being free. The rider grants indestructibility, not hexproof or protection, so a bounce or exile effect still unravels the whole play cleanly.