Shadows of Forbidden Gods - The Horrors Beneath (AppID: 2855250)

A New Dark God

The Evil Beneath is a vast god-thing, larger than entire continents, which feeds off death. Grow it across the underground map, and use its powers to cause death and destruction. As humanity falls, devour the bodies to grow and strengthen yourself, preparing for the final war against the human remnants when they finally learn the terrible truth.

The Underground

An entire new map layer is added in this DLC, letting you venture beneath the kingdoms of men and elves to undermine them from below. Underground, Dwarves are locked in a constant battle with the evil Cthonians, and can shift the balance of power in favour of the Alliance, or in favour of the dark if you exploit their weaknesses. Dwarves are prone to grudges, and will hunt down anyone holding their crown jewels, potentially starting a war which will ruin any hope of the Alliance opposing you.

Two New Agents

Two new agents are added, the Spellbinder, who is able to cripple heroes, and the Exiled, who emerges from the tunnels to seek prey on the surface for dark sacrifices in their underground lair. These agents deal with the new Evidence mechanic, which lets your crimes go unnoticed for a while, as long as you can prevent heroes from investigating the Evidence you have left behind.

The War Spills Underground

Humans and orcs can both learn of the underground and begin colonising it, to continue their constant warfare in these new domains. Lead your hordes to victory as you build up your forces beneath humanity's feet, or suffer as humans expand rapidly into the new territory you have opened up for them.