The Storm Blot is supposed to be the main antagonist in Epic Mickey. It was supposed to appear, but it got scrapped. He was replaced by Oswald, making the game the main deuteragonist. He is mentioned in Epic Mickey: The Power of Two.
Concept Art 1
In this picture, the Storm Blot is bigger than the Shadow Blot. On the picture, you can see characters, such as Horace Horsecollar, Clarabelle Cow, Genie from Aladdin, Livers Lips McGrowl from Country Bear Jamboree, and Dopey from Snow White.
Concept Art 2
In this picture, the Storm Blot is shown using the Shadow Blot's patterns such as sending Blotlings.