Yosei, the Morning Star

The death trigger is the entire point, and it inverts how a creature is supposed to die. Trading with most fatties hands your opponent a clear board; trading with this one buys you a turn and a half of paralysis: they skip an untap step, and up to five of their permanents get tapped down on top of it. That is a Time Walk fragment stapled to a flyer, payable the moment the body dies. The design implication is that you stop protecting it. A 5/5 flyer for six wants to block, chump, or get sacrificed, because every one of those outcomes advances your clock and stalls theirs. The legendary tag is what kept that from spiraling out of control in the era it came from, but it also opened the loop that defined the card's competitive life: pair it with a reanimation or recursion engine, kill it, bring it back, kill it again, and the opponent never untaps. That recurring lock is the lineage this card sits in, the white half of a graveyard engine rather than a fair midrange threat. Read straight, it is a defensive tempo swing; read as a sacrifice payload, it is a soft prison you assemble one death at a time.