Gratuitous Space Battles is a mix of real-time strategy and tactics of Tower Defense, altogether featuring a science-fiction setting of space warfare.
The players find themselves taking the role of the high command of the space fleet, where your strategic placement of each ship and carefully prepared tactics ensures victory in the upcoming battle. The battles, as the name implies, lack any backstory whatsoever, as the game presents them as different skirmish maps. Different surroundings and different fleet compositions help achieve victory, but the enemy also uses environmental hazards as the means of preventing the player from winning. The battlefield is non-interactable, which means the player has to plan each movement.
The game features a multiplayer mode, where players can battle each other using their customized ships, with different upgrades allowing to gain an edge over the enemy. The stunning 2D graphics ensure that the look of each ship type is unique and memorable, and the battle itself shines with colorful explosions, laser beams everywhere and almost realistic crashes of defeated spacecraft.