War

War is one of the Four Horsemen of the Apocalypse, along with Famine, Pestilence and Death. He wears a pure gold ring, which is unique amongst the three rings belonging to his brothers as it lacks a gemstone.
His ring along with Famine, Pestilence and Death's form together as a key to Lucifer's Cage, his ring, while connected with the other three rings, is merged in the direct center of the Cage's key. When War arrived on Earth; he used his ring's power to make himself look like a man named Roger. In other words, War made Ellen, Jo, Dean and Sam perceive him as a human by altering their perception.
War is the first Horseman to appear in the series. He turns an entire town against themselves by making them think there are demons when there are none. War claims that Famine, Pestilence and Death are his siblings. He is also known as Wormwood.