Forts is a physics-based RTS that has you going head to head with other forts.
The objective is you want to build onto your fort continuously, adding more layers and weapons to destroy your opponent's fort before they dismantle yours. There's a level of complexity with the game that makes it interesting enough to keep you going to figure everything out. After you get the gist of the game's mechanics and you don't feel like battling the A.I anymore, you can hop into PvP (PvE multiplayer also available) to test your mettle against others.
I'm not the biggest fan of RTS' but I tried to keep an unbiased mindset while playing, and there was genuine fun to be had. I'd recommend it, at least to try it out.
2.0