Play Parasitus first. It's better than Invasion by a lot and you can understand the jokes in Invasion where the devs cry about no one buying Parasitus for 240. Also, Invasion is about 1/4th as long as Parasitus and the ending is more dev butthurt over Parasitus.
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Just wanna be sure, you're talking about parasitus; ninja zero, right?
Yeah, I should have added the subtitle to avoid confusion. But yeah, it's one of my favorite Indie games. Invasion is somewhat of a sequel to Parasitus (made by same guy/company), but I find the first game the best.
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