TITANS is the huge stand-alone expansion to the already massive-scale RTS Planetary Annihilation, which includes the base game and adds tons of new features: 

Devastate your enemies with 5 massive Titan class super units like the earth-shaking Atlas bot and lightning-wielding Zeus airship! 

Expand your strategic arsenal with 16 new units such as versatile Hover Tanks, indomitable Orbital Battleships, and voracious Nanobot Swarms!