Cross-X on 28 March 2013
Don't have Xbox so I can't say Halo since I never played them.
But my vote goes to Resistance 2. Regardless of many people hating on it, I had ridiculous amounts of fun and joy out of Resistance 2's mutliplayer and Co-Op. Not to mention the Single Player stuff as well. Plus it had online split screen which is a huge thing for me.
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