phenomen a book

When Jack comes across the secret to eternal life in the back of an ancient library he gets more than he expects. As long as he keeps his Vita bar full he can live forever but should that bar run out he will die forever. To keep the bar full Jack must sacrifice the lives of others, the more powerful the life sacrificed the more vita he regains. With this knowledge Jack sets off to kill all the gods in hopes of finding a way to become truly immortal.