Cephalaspis

Cephalaspis was an agnathan vertebrate so named for its armored head. It probably lived life as a bottom-feeder, sucking up minute organic particles in the substrate. In Walking With Monsters, it was pursued by the monster chelicerate Brontoscorpio in the Silurian period, and was remarked as the first ever animal with a complex brain, despite that it lived from 415 to 388 mya, in the Early Devonian, and that other animals had equally complex brains. Later, a school of Cephalaspis migrated to a pool of water that has been described as their "birthplace" in order to spawn, themselves; the pool is landlocked and the Cephalaspis school make it by emerging from the water in a highly unrealistic fashion.