| I don't know about the best game I've ever played, but it is a really fun game. I enjoyed the story, except the major cliffhangers at the end.
Horde mode is pretty fun, but most of my friends don't like it.
The online needs some serious work. Last time I was on, there were 5-15 minute waits to get into a match if you're alone, and when you're with a party it's even longer. The only reason I stopped playing is because I'm waiting for a matchmaking fix.
All in all, Gears is an awesome game. I love the over the shoulder shooting, and unique weapons. Massive fun online chainsawing someones arms off and listening to them complain like little girls that "the chainsaw is a cheap weapon", but hey, not my fault if you don't backroll and shoot. It's all GoW1 fanboys who shotgun whore and haven't accepted that running up to me will not work. | 
Gears2 
Linear Mode
