 Writer Steven DeKnight , who wrote for Marsters when he was portraying Spike on Buffy the Vampire Slayer , used a different approach for Marsters when writing for him as Brainiac . Spike is more " snarky " , and DeKnight felt Fine is more sincere , and a " straight @-@ ahead classic villain " . This different approach to villainy worked well for Marsters , who wanted to show people he could portray characters who were not just another " Spike " . Marsters describes Brainiac as " a murderous robot " with no remorse over his actions . According to Marsters , the character is an " intellectual " who is focused on what he wants . The actor was drawn to the series because of the " refreshing " take the producers had , as well as an appreciation for the idea of a show about Clark 's journey toward becoming Superman . 
