Well, I finally decided to watch all of the cinematics for Ground Zeroes last night on YouTube. I still have yet to play the actual game, which I will buy when there's a price drop that I find reasonable enough. But, I have to say, I wasn't impressed by Kiefer's performance at all. His portrayal of Big Boss seemed rather wooden and subdued compared to Hayter's in the previous games. I also don't fully understand the need for the "dark" ending, and I think it was done purely for shock value that served no purpose beyond that.
But, beyond general impressions of Ground Zeroes, I've also noticed inconsistencies with the themes of MGS V that just aren't making any sense to me, and I'm pretty sure that this game will serve to retcon the series further away from its established canon in MGS 4. Firstly, Big Boss broke away from The Patriots and Zero after "Les Enfants Terribles", and the two of them went to war with one another because of differing ideologies on The Boss's legacy. It had absolutely NOTHING to do with Big Boss seeking revenge for his fallen comrades like the proposed themes in MGS V. Zero believed that the world should be united through the censure and control of information (eg. the role of the Patriot AI satellites), while Big Boss envisioned a world of PMCs where men were free to fight their own wars.
With that said, the whole "revenge" plot of MGS V just falls completely flat on itself, because Big Boss and Zero were just two men - obsessed and bent out of shape, in a heated religious battle over The Boss's will.
Of course, it's still left to be seen what's the deal with Skull Face and XOF. Maybe their roles in MGS V will help to make sense of this mess, or maybe it won't
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