1.The GTA Series

2. COD series. 

Easily Modern Warfare 2. I still can't believe how it got 94 meta score. Single player campaign is one of the worst campaings I have ever played (zero plot and character development) and we have seen same kind of multiplayer already ages ago.

Oh geez there's so many in my opinion

- Modern Warfare 2

- Gears of War series

- God of War series

- Metal Gear Solid 4

I'd list more but I gotta go get ready for class

Halo series hands down.

all halo series..

repeating gameplay style after so many series

yet never get bored by any reviewer

guess all reviewer were its fans after all

Mega Man 2. 'Twasn't bad, or even average, but it doesn't deserve all the praise either. MM3 > MM2 in basically everything. (Including the music. Yeah, I said it.)

GTA4

with runners up including Halo 3, MGS4, ME2, Oblivion