The Spider-Slayers are a series of fictional robots in the Marvel Comics universe that were specifically designed to hunt down, capture, and/or kill Spider-Man. The first series of robots were originally designed and built by Dr. Spencer Smythe with the financial backing of J. Jonah Jameson who piloted them for the pleasure of personally hunting the superhero he hated for capture. However, Spider-Man always managed to defeat each robot in turn. Smythe's continual efforts to perfect his machines backfired on him, leading to himself being fatally contaminated by radiation poisoning from the building materials of his creations.