: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.
Drop Heartless Hidetsugu, give him haste, and tap him to slash the table's life in half on demand. From there you assemble a one-shot kill with a damage doubler that hits opponents harder than you, a repeatable untap to chain halvings, or a life-loss amplifier like Wound Reflection. The deck is a focused combo/burn engine that races to convert one or two Hidetsugu activations into a dead table.
A single tap can erase 20+ life from every opponent at once, scaling perfectly against high-life and lifegain pods
Mono-red gives access to the format's best fast mana, haste, and recursion to deploy and protect the engine repeatedly
Multiple distinct win lines (doublers, untappers, life-loss multipliers) make it hard to fully disrupt
Cheap to cast at 5 mana and immediately threatening the turn it resolves with haste
The ability is symmetric and damages you too, so naked activations can kill or cripple yourself
Heavily reliant on a combo piece sticking; bare Hidetsugu just softens the board
Opponents at odd life totals or with life-total-locking effects blunt the math
Vulnerable to creature removal, taxes on activated abilities, and graveyard hate against recursion
Lifegain or fog effects on the kill turn can leave you exposed after you've burned yourself
Haste plus hexproof keeps the commander online and protected from targeted removal.
Add fast mana (Sol Ring, Mana Crypt, Jeska's Will) and tutors like Gamble and Imperial Recruiter to find Umbral Mantle or your protection piece consistently. Round out redundancy with multiple untappers and a self-protecting layer (Platinum Emperion, Boots/Greaves) so a single removal spell doesn't end your turn. Trim slow stax and durdle cards in favor of cheap recursion (Faithless Looting, Underworld Breach) to rebuild Hidetsugu after a wipe and shorten the clock to a turn-three or four kill.
Legendary Creature — Ogre Shaman
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