Warhammer 40,000: Dawn of War - Dark Crusade

Summary pulled directly from Steam - Some text may only be applicable to Steam platform

Deep under the central desert of Kronus, a vast honeycomb of skull-lined tunnels and funeral chambers house the awakening Necron menace. Eons ago, these were the boulevards and squares of a great necropolis built to house the bones of the races who had fallen to the Necrons, and ultimately were where the Necrons themselves retire to spend eternity. Over millions of years, sand and rock had covered it all until ill-fated excavations awoke the deathless.
Play any of seven races, striving for control over Kronus. Take other races' strongholds by winning challenging battles on various maps individually associated with the respective strongholds.

New Races
Take command of two new playable races: Tau and Necron to unleash massive carnage across the frontlines of battle.
Expanded multiplayer
Dominate opponents online across 12 new multiplayer maps - with up to 8 players battling it out for supremacy.
Deep single player campaign
Conquer the planet of Kronus any way you choose - leading any one of seven races on an epic crusade through an all-new, non-linear single player campaign where you can experience unique storylines from each race's perspective.
Customization
Customize your hero's weapons, items and abilities as he grows in power and influence. Personalize your army with a variety of insignias, squad colors, banners and names.