Hmm.
5/10.
Pretty smack-bang in the middle, because there are a variety of things good and bad about it. I have a hard time siding either way. The good would be Mercenaries, Lost in Nightmares, the presentation, and the core game from RE4 still being awesome. The bad would be it being RE4 but less so with worse mechanics, the entire plot, the length, the shift to standard third person shooting, and most importantly, the lack of scares and atmosphere.
The core mechanics are solid, which makes it fun, but it really leaves a bad taste in the mouth. Also, co-op is both a blessing and a curse. It is quite fun, but it ruins the single player.
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^Poorly disguised anti-caps sig