Nightmare

Nightmare (originally Saichasika) is a fire-elemental dragon and one of Ichiro's many dragons. It was only used once as an ambush by Ichiro in the battle against Hikaru Himuro. It later defeated Hikaru's Dragon Kokao but that the Kokao was quickly revealed to be only an illusion created at the very beginning of the battle and the real one, which hiding at behind since begun were defeated Nightmare as well. It has an alien-like appearance.