King Arthur

King Arthur was an legendary human figure of Great Britain, as well an major figure in Prequel Amphibia. He's been mentioned multiple throughout Prequel Amphibia by King Andrias to Samuel Colt has someone who once taken and used the Calamity Sword, an powerful artifact said to harness extradimensional energy and warps spacetime to destroy their enemies in Earth's Early Middles Ages before it returned to Amphibia.