Clash of the Paragons

Each opponent loses three times X life. You gain life equal to the amount of life lost this way. Creatures you control get +X/+X and gain first strike, vigilance and indestructible until end of turn.
And as the tenth day passed, Serra faced her mortal nemesis, the Bane of Life and the Slayer of Dreams, Karolys
--The Tale of Ten Eras