Waruder is a robot samurai assassin contracted by SHADOW to kill Ichiro and a recurring character in Kikaider 01. He likes children and is afraid of dogs.


He was initially hired by Big Shadow but because of his fear of dogs, Big Shadow orders Hakaider to kill any dogs near SHADOW's headquarters.

As the series goes on, Waruder develops feelings for Mari, but never fully understands them.

Waruder eventually challenges Kikaider 01 to a final duel and gets defeated.