Jacob Marsh is a villain in the video-game, "Call Of Cthulhu: Dark Corners Of The World" and was a high-ranking citizen of Innsmouth with connections to the Order Of Dagon: he sought to kill anyone who got in the way of the Order and acted as a mini-boss as well as a recurring opponent in the game.
Jacob Marsh first attempts to kill the player-protagonist via trying to toss them into a grinder using a treadmill, then he tries to kill a fictionalized version of the famous FBI agent Hoover via throwing him into a molten vat of metal: the latter acts as a mini-boss stage since the player must act quickly to save Hoover's life or risk a "game over".
Jacob Marsh is part of an infamous family who are all corrupted due to the influence of the Deep Ones, alien creatures from beneath the waves who have a great deal of power over Innsmouth.
After a dangerous game of cat and mouse Jacob ambushes Jack, knocking him out and leaving him in the refinery as a Shoggoth is unleashed: forcing Jack to evade the monstrosity - in the chaos Jacob steals Jack's weapons and escapes.
However it is later revealed that Hoover and his crew captured Jacob Marsh as he tried to escape, he is seen cursing Hoover in the name of Dagon and swearing vengeance as he is led away to his impending prison sentence.