Cover for the DeepWars rulebook, published by Antimatter Games.
About the game:
DeepWars is a 28mm scale tabletop wargame set in an alternate history of Earth where fortune seekers, scientists and adventurers have discovered a lost land with an underground sea miles beneath the frozen surface of the southernmost continent.
Here you can find more about this game and see more artwork: [link]
And right now they are running a kickstarter pledge for developing a new version of its predecesor, ShadowSea, check it out! [link]