DuckTales the Movie: Treasure of the Lost Lamp

Scrooge McDuck travels to the Middle East to inspect a recently discovered treasure chest he is certain contains the treasure of the great thief Collie Baba, accompanied by Huey, Dewey and Louie, Webby Vanderquack, and Launchpad McQuack. Although initially disappointed when the chest seems to only contain old clothes, Scrooge is excited when an ancient treasure map is found in the pocket of an old robe. Guided by the thief Dijon, they set out to find the lost treasure, not realizing that Dijon actually works for the evil sorcerer Merlock, who desires something Collie Baba owned. The group discovers Collie Baba's treasure in a sand-covered pyramid. Webby sees a lamp in the treasure, which Scrooge lets her keep since it does not hold any value.
After packing up the treasure for transport, Scrooge and his group are trapped in a room full of monstrous scorpions by Merlock and Dijon, who steal the treasure. However, Merlock discovers that the lamp has been stolen; he drags Dijon with him to locate it. Scrooge and his friends manage to escape from the pyramid and, with nothing more than Webby's lamp, depart for Duckburg.
Days later, the children discover the lamp holds a Genie. Ecstatic about his freedom, the Genie grants the four children 3 wishes each; to trick Scrooge, he poses as the boys' Woodchuck scout friend Gene. Their wishes include a baby elephant (which runs amok through Scrooge's mansion) and a giant ice cream sundae, among other things. Fearful of a bird flying by at night, Genie tells them about Merlock, who used his wishes for eternal life and the destruction of Atlantis and Pompeii, which were both popular vacation spots; Merlock's magic talisman, which allows him to take various animal forms, also overrides the lamp's rules, granting him unlimited wishes. Collie Baba stole the lamp from Merlock and hid it away with his treasure, and Merlock had spent the centuries since searching for it. They must prevent Merlock from obtaining the lamp or the world will suffer.
The next day, Webby uses her last wish to bring all her toys to life, which forces the children to reveal the Genie's true identity to Scrooge. Wishing to impress the Archeological Society at their annual ball, Scrooge wishes for the treasure of Collie Baba, and brings the lamp and the Genie with him to the ball. He is followed by Merlock and Dijon, who violently ambush Scrooge. In the ensuing struggle, Scrooge mistakes a gravy boat for the lamp and leaves the lamp and the Genie behind, after which they both fall into the hands of Dijon, who is convinced by the Genie to keep the lamp instead of giving it to Merlock.
Having wished for Scrooge's fortune, Dijon takes possession of the Money Bin and has Scrooge arrested for trespassing. However, Scrooge is immediately bailed out by Launchpad, his nephews, Webby, Mrs. Beakley and Duckworth, who agree to help Scrooge set things right. Scrooge, the nephews and Webby infiltrate the Money Bin in an attempt to steal the lamp, but are stopped by Merlock, who recovers the lamp. With the Genie under his control again, Merlock wishes for the "disloyal swine" Dijon to be turned into something "fitting" (Genie turns him into a pig), then turns the Money Bin into a fortress, which flies into the air high above Duckburg. When an indignant Scrooge threatens him, Merlock wishes him "out of my house", and a reluctant Genie raises the wind to send Scrooge to the edge of the fortress, hanging on for dear life. The nephews use a slingshot to knock the lamp out of Merlock's hands, tossing it to Scrooge, who loses his grip and falls towards the earth. Merlock recovers his talisman and pursues as a gryphon, grappling with Scrooge in the air. Scrooge knocks the talisman from Merlock's hand, and the sorcerer falls to his doom.
Recovering the lamp, Scrooge uses his second wish to return himself, his family, and his Money Bin back to Duckburg. Back in the Money Bin, Scrooge declares that he's had "enough of all this wishing" and threatens to use his final wish to bury the lamp where it would never be found again. Instead, he wishes for Genie to become a real boy. Without the Genie, the lamp crumbles to dust. While the children play with their newest friend, Scrooge discovers Dijon, recovered from Merlock's wish, stuffing his trousers with his money. Scrooge chases him outside, yelling "Somebody stop those pants!"

Question: At the ball, Scrooge is ambushed by Dijon, and who else?
Answer: Merlock