Dr. Doom and Dr. Strange: Triumph and Torment
Dr. Doom's origin stories tell us that his mother, Cynthia, was a sorceress who sold her soul to the Devil (Mephisto) for power. After she passes away Dr. Doom spends his entire adult life making attempts to rescue his Mother's soul from hell. Doom's trips to hell are documented in Astonishing Tales #8, Iron Man Doomquest #150 and, finally, in Dr.Strange and Dr. Doom: Triumph and Torment.
In exchange for his mother's freedom, Dr. Doom sells Dr. Strange's soul to the Devil (Mephisto). The act of selling another person's soul is totally malicious-and is the same act that earned Loki his "God of Evil" title.
When Cynthia's body is restored, and Mephisto has taken possession of Dr. Strange's soul, she becomes aware of the malevolent sacrifice that her son has made. She does not condone his actions and refuses to leave hell. Her soul becomes light and pure, which Mephisto cannot stand, and she is allowed to ascend to heaven. Dr. Doom and Dr. Strange escape hell, having bested the Devil.
When Dr. Doom orchestrates the deal with Mephisto, for Dr. Strange's soul, it shows us the true ruthlessness of Doom's character.