MAGNUS CHASE AND THE SHIP OF THE DEAD (BOOK 3)

My name is Magnus Chase. These days, I'm one of Odin's immortal warriors, but that doesn't stop people trying to kill me all the time. Loki the trickster god is free from his chains. He's put together a crew of giants and zombies to sail Naglfar, the Ship of the Dead, in a battle against the Norse gods. If he succeeds, the final battle of Ragnarok will extinguish all the worlds. With help from Percy Jackson and my cousin Annabeth, I have to sail across the oceans to stop him.
The only problems are the angry sea gods, hostile giants and evil fire-breathing dragon in the way. To stand any chance, I must find a magical elixir so deadly that it will either make me powerful enough to defeat Loki and put him back in chains for good ... or destroy me entirely.