Skeletal Executioners are a larger, more powerful version of skeletons, instantly recognizable by their red hoods, huge shoulder pads, and the massive headsmen axes they wield. Undead or not, those axes are heavy, and the executioners drag them behind, leaving a trail of sparks. They only pick up the axes when they are about to use them, and they use both arms to deliver vicious overhead chops with their weapons. Their attack rate is fairly slow, and if you can dodge their first swipe you can almost always finish them off before they can take a second one.
Skeletal executioners have a short range charge attack that they finish with a devastating chop of their axes. Being hit by one won't actually kill a character in a single blow, but it's quite painful.
Media
See screenshots and concept art of Skeletal Executioners in the Image Gallery.