Okay first off Breakfast Of The Gods is pretty funny – a brutal over-the-top Sin City style comic featuring… breakfast cereal mascots as characters.
But as a parody of famous trademarks, I kind of wonder if creator Brendan Douglas Jones is walking on thin legal ground. When a trademark is famous it's not a question of confusion, even "dilution" is sufficient to create an action. Fair use might save the day even then, but the ultimate answer isn't obvious to me. In any event, just to be safe check it out before General Mills notices it!