The Masked Killer is an enemy in Ninja Gaiden (NES) and Ninja Gaiden II: The Dark Sword of Chaos. They are an obvious spoof of Jason Voorhees, a popular serial killer in horror/slasher media.
Masked Killer in Ninja Gaiden II.
Ninja Gaiden[]
First appearing in Act 4-3, Masked Killers are potentially one of the most dangerous enemies in the game. They are a palette swap of the Banshees and Jack O' Murderers and Mace Men and do the same thing, their weapon of choice being axes. Both their contact and axe attacks do 1 damage, and they are best defeated using sub-weapons to work around the axes.