"It's a matter of concentration. So the farther along the stream and the smaller the portion of the fouled water is to clean the safer it is. There are ways to treat fouled water that kill the organisms in it but I don't know exactly how they work. Where Sheppard and I come from it's an entire field of study. Boiling water will generally render it safe but that's a lot of work to do for every bit you choose to drink, alcohol can also have the same effects but I don't remember exactly how strong a drink needs to be for it to be basically safe."

"Those parts we know, though if there's a principle underlying them I suppose that might be useful. ...The size of the fouled portion being relative rather than absolute would be surprising, possibly for supernatural reasons; I've seen substantial reservoirs made diseased with a fairly small contamination we didn't catch in time. We might be able to do something with the knowledge nonetheless."

"The body is the best place for the microorganisms to breed but it isn't the only place and so especially for still water it's possible for a relatively small contamination to breed into a much larger one."

"I don't know what's in them but we do carry tablets intended for treating small amounts of water for use in the field. My survival training suggested boiling water instead if possible though, both because it was supposed to be more effective and to conserve supplies."

"We'd appreciate a look at them, probably, but if it's a specialist matter for your people, and none of you know any of it, I wouldn't say it's a priority. I don't know offhand who I'd want to look at it, unless we asked the dwarfs."

"Fair enough, I'm not actually sure what other technologies would be helpful. I'm fairly familiar with the history of weaponry on my world but that's something I'd want to wait to share until we know each other better. I'm also not sure how applicable it would be to the battles you're fighting. We didn't have magic when we were using the sort of guns I saw you holding earlier and I imagine that changes what is and isn't useful."

"Yes, that's understandable, though I'm very curious about the design of your guns, with the small bore and tall stock and all. Against most enemies our weapons are much the same as against other ordinary men; for others, mostly daemons or half-ascended Chaos worshipers, blessings or symbolic significance can have more impact. Winged Lancers pass down their arms over the generations and this makes them, probably, a little bit blessed, and so their charge is more effective against daemons than a new man's lance. The same with the Ursunite bear riders, and the Ungol's family bows, and so on. Cannon hit harder, of course, but something about the nature of daemons sort of throws off the damage as being contrary to their nature, like they are a story that only consents to be ended in certain ways."

"That sounds frustrating to deal with." He wonders if Wraith stunners or Ronon's particle Magnum would get around that. He doesn't see a reason why the firearms would.

"Extremely. Weight of fire, or enough ordinary sword blows, can bring them down. Other than the very greatest they're resistant, not immune. But fighting daemons is much worse than beastmen or greenskins even if they're in smaller numbers, and would be even if their weapons weren't more deadly. ...Also anything strong enough for its god to give it a name will be back and fighting again in a century, even if we kill it. But honestly we just try not to dwell on that part."

"Enemies that refuse to stay dead are always annoying. Thankfully I haven't had to deal with any that literally can't be killed though."

"Bringing anything here from the Realm of Chaos takes either an army overland with sorcerers, or something like what you saw when you arrived, with human sacrifice and ritual and all, so sending them back is a reasonable victory. But you see why we're not inclined to optimism."

"Yep that would do it. I've managed to wiggle out of enough tough spots that I've learned it's important not to give up hope but it doesn't seem like you've done that."

"Strong wills and fatalism, at least, don't make us stop trying. Actually, what you said reminded me: What can you share about the Wraiths you mentioned? They're physical, and vampiric, but called 'wraith'?"

"That's what we call them at least. I don't know what they call themselves. We haven't had occasion to talk with any. I think I mentioned before that they feed on people's vitality somehow. I'm not really sure how it works but someone in the prime of their life can change to looking like someone at the end of a long life in less than a minute if they're feeding as fast as they can."

"They can also restore people to youth, it's something they do rarely to reward the humans who become Wraith Worshippers. Or as part of torturing people."

"Eugh. I've never heard of our vampires healing their victims, though I suppose I wouldn't be shocked to hear they can. Do they feed often?"

"I'm not sure. Nobody is really able to safely observe them enough to know. What we do know is that they hibernate sometimes for centuries at a time when they've taken too many of us and there aren't enough to sustain them. Sadly their last period of hibernation ended a bit over a year ago."

"Hibernate collectively? That's interesting. Vampires here can sleep - well, 'sleep' - for very long times, especially if they've been killed and are recovering, but outside a major Vampire War that kills several leaders, almost never as a group."

Though he's not particularly believing her, as the one person here who is potentially hostile even if this isn't a Chaos trick. It's still data.

"They leave watchers awake to warn them of any threats and to ensure we don't forget about them, to ensure we don't ever believe ourselves safe or get powerful enough to challenge them. Until Sheppard's people came I didn't believe anyone could stand against them."

"Because of inadequate weapons? Numbers?"

"The Wraith are stronger individually but that can be overcome. Their true power is in their darts, and their larger starships. Most of the peoples of my galaxy don't have aircraft or weapons that can damage even a single dart and en masse they are even harder to defend against. And if a world developed enough to fight the darts, a cruiser or a hive would simply bombard them from orbit."

"To be clear, wraith darts aren't projectiles; they're flying craft that can shoot bursts of fire, for lack of a better word, and use culling beams to simply disappear people on the ground beneath them to be rematerialized later inside of their hives where they don't have a chance to fight back."

'Peoples of my galaxy', and they still weren't beating the vampires. That's sort of terrifying.

"Are the culling beams understood to be magic?"

"No they're technology, they operate on the same principles as ring transporters, Asgard beaming and to a lesser degree Stargates." 

"Interesting. There's not much magic in your galaxy, is there? Even your souls have less than normal."