Could it be that Metal Gear Solid 3 is quite dated in the gameplay departement now? I did enjoy MGS1 and MGS2 a lot in that front...
In MGS3, there were so many cutscenes and I LOVE Kojimas cutscenes but in MGS4, every moment : I was like: Damn.. I wish I could play thi.. oh hello! AWESOME
MGS3 had not a single thing like that aside from the Shagohod battle which I honestly felt was ..not great.
And oh I wanted such an epic final fight with The Boss but I didn't enjoy that AT all.
I guess what I am saying is I was let down in the gameplay departement in my opinion. I can understand the Story probably is great, but I was doomed from the moment I played MGS4. I just wanted to see if there's anything else that I missed. Perhaps I did it wrong.. I don't know. I just can't believe how underwhelmed I felt. But like I said, I knew the plot.
