City-Storming Beast is the main boss in the Echoes of Eternity raid event. Main raid bosses are hit for normal damage and the player has 2 hours to defeat them. It's hp varies depending on its level:
Level Maximum Hit Points 1 100 2 600 3 900 4 1000 5 1500 6 3000 7 6000 8 10,000 9 15,000 10 20,000 11 30,000 12 40,000 13 50,000 14 56,000 15 62,000