The final Aquazone subtheme in 1998 was the Stingrays, which were fish-like mutants and enemies of the Hydronauts who used underwater vessels that resembled sea creatures. The villains included Commander Manta Ray and Raven Ray and the subtheme contained 5 sets and set 6109 Sea Creeper was the same as set 6140.
1998 LEGO Sets
In 1998, LEGO released several new sets and themes, including the LEGO Star Wars theme, which was based on the Star Wars movies and featured models of characters, vehicles, and locations from the films. This theme was extremely popular and helped to boost LEGO's sales and popularity. 1998 was also the year that LEGO introduced the LEGO Mindstorms theme, which was a line of sets that allowed users to build and program robots using LEGO bricks and a computer.