Reapers
I been meaning to post this here. On Virmire you have that little chat with Sovereign, who claims it "transcends your very existence" and "the reapers are part of a cycle that cannot be stopped" and "it doesnt matter what reapers are called, they simply are."
Of course this forshadows new antagonists for Mass Effect 2. I wonder what the reapers will be like.
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