Luke Castellan

Luke Castellan is a son of Hermes. He was once the counselor of Cabin Eleven. Annabeth Chase, Thalia Grace, and him all were runaways from home, and made their way to Camp Half-Blood. In The lightning Theif he betrays Percy, joining Kronos in his army against the gods. He is made the leader of the war, Kronos after even used his body for the process of coming to full power. He swam in the river styx, making him impossible to kill unless knocked in his "achilles heel" In the end he betrayed Kronos, taking what control he had to kill himself, ending Kronos alongside him. The line cut in the Lightning Theif was actually his all along.