Tiuri, Unshackled Confusion

{1}{r}, Pay 2 life: Tiuri gains +2/+0 and menace
until end of turn. If you have 5 or less life, instead
he gains +4/+0 and gains lifelink until end of turn
At beginning of your upkeep, you may sacrifice another creature. If you do, Tiuri breaks free, becoming unblockable until end of turn dealing 2 damage to each opponent.
Echoes of a forgotten melody linger where his mind wanders, lost chords weaving the tapestry
of his untamed thoughts.