Oooh, I like zerg >3> ... actually, can we pretty much invent alien species for the setting for a character to be put into this mission? XD

That said, isn't there a limit to what or how fast the 'X' can infect? or is it literally canonically an infinitly infectious thing that somehow nothing can be immune to? XD [neverminding that Samus evolved to be immune to, or at least resistant enough to destroy it XD]