Stellaris: Apocalypse

Apocalypse is a full expansion that redefines stellar warfare for all players with a host of new offensive and defensive options. Destroy entire worlds with terrifying planet-killer weapons, fight against (or alongside) ruthless space pirates, and maybe discover a few non-violent features as well.

Features:
THAT'S NO MOON - Wield the new “Colossus” planet-killer weapon – a technological terror that eliminates entire worlds from the universe.
ALL YOUR BASE ARE BELONG TO YOU - Lead your fleets with enormous “Titan” capital ships and fortify key systems with massive orbital installations to make your homeworld an impenetrable bastion among the stars.
PIRATES OF THE CONSTELLATION - Watch out for Marauders – nomads who raid settled empires for resources. Hire them as mercenaries but make sure they don't unify against you!
NON-VIOLENT FEATURES - Use new Ascension Perks and Civics along with Unity Ambitions that offer new ways to spend Unity and customize your development.