With another gem, Vreedl becomes a fish man and again evades the Challs. Finally, with the fourth gem, Vreedl becomes invincible until Ace points out that anyone could become like him through possession of the stone, so Vreedl destroys it, transforming himself back into an ordinary man.; Professor Brandon's assistant Vreedl has stolen the Star-Stone, a device created by an ancient sorcerer, and is stealing gems to place in the stone and give himself powers. The first gem makes Vreedl into a flame man and allows him to start a stampede and delay the Challs while he secures a second gem.; The second gem turns Vreedl into the "Birdman of Djiizari" and with that flying power he escapes the Challs.