I thought the Call of Duty series was getting a little old until they showed off Call of Duty 4: Modern Warfare.
The single-player campaign was more expanded, and better than any other game in the series before it. My favorite was the camouflage mission. However there were also plenty of other tough moments, that were so epic it’s hard to imagine.
I actually didn’t care for the multiplayer too much. People are way too good at it, and it’s pretty much one-hit kills. Sigh.