His attacks include a water jet that knocks players to the back of the boat where the boss fight is situated, where his large tentacles will deal 1/10th of the player's maximum life points per hit. He also has a typeless melee attack, where he attacks with his claws, that hits for 1/30th of the player's maximum life points. The water jet only sprays one half of the boat and can be avoided by moving to the other side. The water jet attack does 1/30th of the player's maximum life points each hit.
After half his health has depleted, Agoroth may temporarily shield himself from attacks and spray acid from above, dealing 1/6th of the player's max life points on contact. The shield blocks direct damage from player, however area of effect attacks (such as Death Swiftness or Sunshine) and damage over time effects (such as Combust or Dismember) may continue to harm him. The damage from acid sprays can be avoided by running away from shaded spots. Players can also run up the ladders at the rear of the ship to be shielded from all attacks, including the tentacles.
After the quest, Agoroth may be fought again in the Ashdale Caves by accessing the Dead Man's chest. Entering the caves after the quest will bring the player directly to the Agoroth boss room and the Dead Man's Chest will be placed prominently in front of the player. Successfully defeating Agoroth again grants a reward of coins, or a Black pearl that gives bonus experience in a skill of the player's choice. The reward can be claimed by searching the chest again after the fight. Non-members are only able to kill Agoroth once per week, while members are able to kill him twice per week. The fight is safe; if killed, players will respawn on the ship at the beginning of the fight, but if all four tentacles are already killed they do not have to be killed again. Although players cannot leave the ship until Agoroth is killed, players can go up the stairs to the section at the back and then exit to the lobby. Exiting in this way does not count as a kill.