Adoroz, Root of Agony

If another creature would die, instead return it to the battlefield with an agony counter.
Creatures with agony counters become 0/1 slave creatures in addition to their other types with,
"At the beginning of your upkeep, you lose 1 life.
{b}{b}{r}{r}, {t}: Put an agony counter on target creature. Activate this ability only as a sorcery.