|Date of Birth:||Unknown|
|Date of Death:||Lucius 2: The Prophecy|
|Cause of Death||Shot with salt laced bullets by Lucius|
Isaac Gilmore was another son of Lucifer and was considerably the half-brother of Lucius Wagner. Not too much is known about him, but in Lucius II: The Prophecy, he is the main antagonist and rival of Lucius.
He was born at St. Benedict Memorial Hospital many years before Lucius was and as an adult, set out to fulfill religious prophecy as described in the Book of Revelations.
After doing unknown evil deeds to sound the first and second trumpets, Lucius made his presence known to him by poisoning the water supply which sounded the third trumpet judgement. Attempting to secure his standing, Isaac found a way to make a meteor fall to earth sounding the fourth trumpet. At the locust farm, he was confronted by Lucius who had released the locusts to sound the fifth trumpet and he then burst into flames after Lucius threw container of salt at him.
Later, he reappeared supernaturally resurrected on top of a building in Ludlow where he tried to kill Lucius with fireballs, but yet again Lucius defeated him with salt content as it was in bullets fired from a shotgun which is believed to have destroyed him.
- Because of how lethal salt was to him as a demon, it is likely salt is also lethal to Lucius.
- At the end of the game, Lucifer remarks that he has many sons meaning there are more demonic brothers "related" to Isaac and Lucius.
- It is possible that his name and his burning of cornfields is a reference to the Children of the Corn Series as the main antagonists are both named Isaac.
- Isaac's appearance also holds a similarity to Courteny Gains' portrayal of Malachai from the 1984 adaptaion of Children of the Corn. This is ironic because Isaac Chroner, the main antagonist of the Children of the Corn, bears resemblance to Lucius.