Other mistake: Grey Matter held his breath underwater to save the drowning man, but he has gills so that he can breathe just like fish.
Grandpa Max Tennyson: Being a hero isn't about letting others know you did the right thing, it's about you knowing you did the right thing.
Ben Tennyson: What were you just doing, reading greeting cards back at the Mega Mart?
Grandpa Max Tennyson: Well... yes.
Trivia: 4-9 "Ben 10 vs The Negative 10 I": The holiday camp where Cooper is picked up by Max Tennyson looks quite like Camp Opinicon from season 2's "Camp Fear".