The Placoderms ("plate skin") are a class of extinct jawed vertebrates which are - by those few laypeople who've heard of them - dismissed as being a bunch of sluggish has-beens which were somehow easily outcompeted by primitive sharks and primitive bony fish. That is, except when people talk about the "first vertebrate superpredator," the bus-sized Dunkleosteus, which is popularly imagined as being akin to a swimming dumptruck of death that munched on primitive sharks like fishy carrot sticks. They are also known as "Panzer fish" in most German-speaking countries, but only a very few had body patterns that included the Iron Cross (most had patterns that formed concentric rings, "measles," or a wood-grained texture).