That's what I thought..he did say that his gravity attacks were more potent than Guyot's in the story, just seeking other opinions. However, you also have to take personality(more aggressive), intelligence and will power into consideration as well. I believe Guyot might have a leg up in those categories, and those certainly help to decide who has the edge. Also Guyot has size and strength over Imakarum as well from what I am reading, Not gravity or energy over Imakarum though as has been stated.