Thread:ShamelessNitpicker/@comment-3581997-20161025073324/@comment-30053419-20161025083948

Not necessarily spontaneous: we know from encounters with Infectees like Schreber that Filth infections can take quite a while if emerging from microscopic exposure. And at least one of the Viking had direct exposure to a rift opened during the Darkness wars. Again, what exactly happened remains a mystery so far: the evidence doesn't confirm that Loki played a direct role. However, it's implied that there's another Dreamer somewhere in the ocean - possibly the one behind the Red Sargassum Dream, if the presence of Draug is any evidence. So, here's my theory: Varangian or one of the other Vikings gets exposed to a nanoscopic dose of the Filth; it incubates slowly, subtly, unnoticed. Eventually, when it comes time to leave, he steers the returning fleet off course to wherever this particular Dreamer is sleeping. We know that Filth tends to crop up around the Gaia Engines due to leaks in the prisons, and we've seen from the exploration of Orochi Tower that at least one source has turned up at sea (via offshore oil-drilling, admittedly). So, mass-exposure to the Filth. Some of them are snapped up right then and there, some return home only to transform there and march off into the ocean. Pure speculation at this point, I admit.