Basic Trope: A mundane substance is mistaken for blood. * Straight: Alice walks into a room and sees Bob covered in blood, but it turns out to be ketchup. * Exaggerated: The room is absolutely soaked in blood, and it all turns out to be just ketchup. * Justified: Alice had heard news of a serial killer and was expecting the worst, and so her mind assumed blood as soon as she saw something red. * Inverted: Alice sees what appears to be ketchup smeared on the table, so she scoops some up with her finger and licks it. It's blood. * Subverted: Alice sighs with relief as she realizes that it has to be ketchup, except that it really is Bob's blood after all. * Double Subverted: ...No, wait, it's fake blood, Bob was just faking the scene to see Alice's reaction. * Parodi