The tower defense genre feels older than it is, with basically only five years under its belt since Desktop Tower Defense and its kin. But its games have seen so many variations to the model and appeared on so many platforms, that it feels very mature in its parameters of game design and implementation. And this is from a genre that has essentially never received a “triple-A” release and most sales come from direct downloads, not on discs or cartridges.

Solo indie developer Cliff Harris of Positech Games is now officially tackling the genre with Gratuitous Tank Battles, a sort of sequel to his popular Gratuitous Space Battles game from 2009. I had a great time playing that game, but didn’t realize at the time that Space Battles, boiled down, really is a tower defense game too. An excellent example on how varied the genre is, even if you don’t realize it.

But Tank Battles is a proper tower defense game with the familiar onslaught of units marching across the screen and grid-based gameplay that veterans of the genre will instantly recognize. It also features an attack mode for most missions letting you experience the other side of combat, and it wouldn’t be a Gratuitous game without an insane amount of unit creation and modification at your fingertips.

We finish off our second annual indie games month with Gratuitous Space Battles, an epic space battle simulator from Positech Games. During our first independent games month last year, we featured Kudos 2, a life simulator also created by the one man team of Cliff Harris at Positech Games. This guy likes his simulators, whether they're of space, life, or Democracy, but Gratuitous Space Battles is a seriously awesome game.

Gratuitous Space Battles is the first game I ever played of its kind. It's almost like one giant, single turn of a board game, or Civilization. Your opponent's pieces are in place and visible on the board, and it is your job to create and deploy a fleet of ships that can combat and destroy them, hopefully while taking minimal losses yourself. Once you click Fight, there's nothing else you can do. It feels very... unnatural at first, like the developer is taking away control of the most enjoyable part of the game. There are explosions and debris everywhere, and you want to be part of the action. But then you begin to realize that the actual simulation isn't the game, but everything before it.

It's fairly obvious that Gratuitous Space Battles is not a game for everyone. There's no real-time micro-management, no hotkeys to quick select a group of ships, and especially no mouse button spamming to get your point across. Gratuitous Space Battles is one of the finest, genre-defining games I've ever played. The game is simply in its own category. I honestly can't give the game a final score because I don't know what to compare it against.

Gratuitous Space Battles was developed for Windows but also works great in Wine on Linux, which is how I played it.