In Inversion, the whole world stuffers from a type of gravity shift in which there are pockets. These pockets have no gravity. There is no explanation as to why gravity is messed up, but it does add an interesting twist on the shoot and cover style game mechanic.
Fighting enemies is quite entertaining thanks to a slew of neat gravity-related abilities that help elevate the gameplay beyond a mere Gears clone. With a device conveniently provided by their would-be invaders, the protagonists can fire pulses of energy that can either increase or decrease the force of gravity at the location they hit. This starts with simple applications like shooting enemies with a low-gravity shot to lift them up and out from behind cover or hitting a heavy overhanging object with a shot of high gravity to make it drop down and crush enemies below.
On the downside, there is a lack of multiplayer. It is not that there aren't decent game options but rather a lack of players. After trying for several days it became frustrating to find a decent game. When I did, I ended up with game modes that forced players to be cheesy and take advantage of map designs and gameplay flaws that make matches extremely one sided.
In the single player, from the start of the game to the end, you'll fight waves of guys, whom are mostly bald, with different sets of armor and guns. There are breaks to fight area mid-bosses (ones with the gravity guns themselves) as well as area bosses (the slave traders). In between fights there are some puzzle elements that involve gravity going from place to place and moving objects out of your path.
Things get significantly more interesting when you gain the ability to manipulate and toss objects that have been floated with low gravity. For instance, you can kill a distant, RPG-wielding enemy by lifting him out of cover, pulling him toward you with the grav-link, performing a melee finisher on him while he hangs helplessly before you, and then grab his launcher to blow up his buddies. Creative players will find plenty of neat ways to wreak havoc with these powers, and it's all complemented with a highly destructible, physics-driven world that begs to be ravaged. The fun is just as devious as it sounds, but sadly, it doesn't come without a price.