Powers: Inferno possesses superhuman strength (Class 5) and durability, but his primary ability is to generate fear in others. He can send crowds of people into a state of frenzy, and can even direct them to attack a specific individual while in such a frenzied state. He can generate convincing illusions, and can take human form (whether this is metamorphosis or illusion is unclear). His powers are directly derived from Mephisto, and can be increased as needed.
Slifer can transport to Hell and back (literally). He can take human form, and he can fly a helicopter.
Bio: Slifer is a demon from the realm of Mephisto.
Notes: Created by...oh, where to start? Slifer was seen in the background (unnamed and in human form) in a story by Gary Friedrich and Jim Mooney. He was fully seen and named (both in human and in demon form) in a story by Marv Wolfman, Doug Moench, and Jim Mooney. Inferno was created by Tony Isabella and Jim Mooney (who is the only common strand in his story).