Merc is the captain of a flying ship who appeared in two episodes: "Raiders of the Lost Shark" and "Beast or Famine". He is also seen at the end of Aladdin and the King of Thieves, when Aladdin and Jasmine finally get married.
Merc comes to Agrabah to have someone help him capture the Beast. On the ship, he puts Abu and later Jasmine on the sand dune, so that the Beast will eat them and he can capture it. After Aladdin and the others find Jasmine, the Beast shows up and Merc throws his harpoon at its tail. The captain then gets on the sand dune and is about to kill the beast when it approaches him. But Aladdin and the others make it run into a rock and become unconscious. The beast is then tied up in front of the palace. The next morning, Merc unties the Beast and he gets on the ship and tells the gang that he's going north and asks Aladdin if he can help him, but Aladdin says that he would rather stay with Jasmine.
Merc is about to kill the Beast, but then someone else kills it and one of the harpoons hits his ship and it sinks. Merc later finds Aladdin and Abu and talks to them about the rat people that captured the Beast and wrecked his ship. Aladdin insists that he has a crew, but the captain says that he doesn't need anyone. He then helps Aladdin rescue Genie and defeat the Shaman. The rat people offer Merc a staff after turning against their tyrannical leader and he becomes their new leader.