Grim Reaper, Lethal Legionnaire

The reanimation payload here is welded to the combat step, and that changes what kind of reanimation it is. Most graveyard-return effects put a body on the battlefield and leave the timing of the swing to you; this one skips the setup entirely, returning the creature already tapped and already attacking, so the tempo swing and the recursion arrive in the same beat. The catch is that you pay for it twice: the to cast, then another on the attack trigger, meaning every reanimation loop costs a full second casting's worth of mana on the turn it fires. That double-tax is what keeps the effect from being oppressive at four mana, and it rewards decks with big, expensive things worth cheating into play rather than a pile of small value creatures. The finality counter does the enforcement: whatever comes back gets exiled the next time it would die, so there is no infinite recursion, no chaining the same threat every combat. Each returned creature is a one-shot, which pushes you toward reanimating the single most valuable target in the yard instead of grinding the same body over and over. As a synthesis of reanimation and haste-granting aggression it sits in a specific and unusual spot: not a value engine to be looped, but a repeatable one-time cheat that turns your graveyard into a sequence of surprise attackers, each paid for in full and each spent for good.