Creeper World is an RTS* that combines constant explosions with slow, methodical advancement by pitting you against hostile fluid dynamics. Your enemy is the Creeper, a mindless, destructive, viscous fluid that spews endlessly from several nodes, threatening to smother your whole base. You use guns, artillery, and aircraft to disintegrate it before it can. Since Creeper's constantly spawning, your guns are constantly firing, creating a steady front line of destruction. To win, you have to destroy the nodes by pushing the Creeper all the way back to its source.

The end result is a noisy curtain of destruction across a slow, methodical game. Creeper World is all about equilibrium: the Creeper advance ends when your guns destroy it as fast as it can flow in. The only way to succeed is to make enough firepower to push it back, a steady process of building a few extra guns to push the front line back, claiming the now-cleared land to produce more energy, then creating more guns to repeat the process anew. The Creeper doesn't throw any surprises at you mid-game; 30 seconds into the map, you've seen everything it'll do, and you can make a good guess about where it'll flow, where you will fight it, and how to win. After that, it's all about slow, methodical execution.

It's a contradiction of mechanics & presentation that works in the game's favor by making a preparation-heavy game exciting, even when you're advancing inch by bloody inch.

If you want to check it out yourself, there are demos available for Mac, Windows and Linux.

*I could see an argument for this being more akin to a tower defense game than a Starcraft-ish RTS, but I feel the game's different enough from tower defense mechanics to justify being grouped in the broader genre.