『Where should we run to?』


  『How about going back to Eis Kingdom? We need to report about the dollmaster and all…』


  Alma pointed at the direction of Eis Kingdom.

  That would be the correct choice if this were a normal war.

  However, it's not.

  『No, if we did that, Relaia Barondom will relax their defense.』


  『I mean there's no need for it anymore right, isn't that better?』


  『It's true that there's no need to keep the defense up, but doing that would be the same as announcing that Eis Kingdom is aware of what's happening in Saihill Empire. It'd be a big pain if our enemy went into hiding because of that… What we need to do here is to find where the enemy is and deal with them swiftly.』


  That said, with the way we're doing things, it's only a matter of time before they find out.

  The demons must be paying attention to me considering the many demons I've slaughtered, so once they realize that we're nowhere in Eis Kingdom and the dollmaster has been defeated, the jig is up.

  We've got to defeat them before they get to that point.

  『You gotta deceive your allies if you want to deceive your enemies, like that?』


  『That's right.』


  『Then we'd better stay away from the border. The demons are probably watching there too.』


  『Yeah. We're heading to the general direction of the empire's capital. Where exactly… depends on the result of this.』


  I took a little bit of water I drew earlier from Storage magic and put it in analysis magic.

  Since the impurities mixed in the water amount very little, analyzing the substance takes time… Should be over in five minutes though.

  『Analysis magic… Is there something in the water?』


  『Almost definitely yeah. Since the imperial water service extends to the whole country. If you mix a special poison that can absorb life force in an upper stream of the waterworks network, gathering life forces from a huge amount of people would be a simple matter.』


  『Oh that's right, then you'd only need to control the waterworks' upstream, no need to install magic tools in the entire country either…』


  Then Ruli stares at the water inside the analysis magic.

  After a little while, she looked doubtful.

  She probably didn't find anything mixed in the water.

  Even if there's poison in it, the concentration is probably so low it's undetectable just by looking.

  If the concentration is high enough to be noticeable by naked eyes, there would have been a big uproar about people suffering from severe illness everywhere in Saihill Empire.

  The demons are able to gather life forces without anyone noticing precisely because the poison they've mixed in the water cannot be detected with naked eyes.

  Even if the scheme could only gather little life forces from each individual, doing that in an entire nation would still net them quite an amount.

  『But that means, we won't know where they put the poison, no? The empire's waterworks network is a closely guarded secret after all.』


  『I guess it's only natural, their enemy nation would go for it if they knew where the center of the water service were…』


  Indeed, the network of these waterworks is unknown… is what we're taught in Second Academy.

  During wars in olden times, enemy nations conducted a search under the assumption that water should flow from a higher elevation, but they apparently couldn't find anything.

  The analysis was complete when I was thinking that.

  Composition of the impurities… My guess is mostly correct.

  『The result is in. The empire's water service has been polluted with poison indeed.』


  『Then our enemy is the waterworks bureau huh… Maybe we could locate where they put the poison in if we do our best to sneak in?』


  『No, actually, I've already found out where they're doing that.』


  I took a huge paper out of Storage magic.

  Then I used magic to draw a map on the paper.

  『…This is the empire's waterworks network.』


  Ruli was surprised to see the paper.

  『You got a grasp of the water network just from analyzing the water!?』


  『Well, it's unlikely to be 100% correct, but it should be in general.』

  Minutes details down to fine branches in every corners of the empire are drawn on the paper.

  But I didn't actually found all this from analyzing water… Or rather, such a feat is simply unfeasible.

  I simply had prior knowledge.

  The 『Great Empire Waterworks』 used by Saihill Empire presently is the exact same thing as the 『Aegis State Waterworks Network』 that was in my past civilization.

  There should be some places where the network got cut off after the civilization perished, but the fact that water reaches here must mean that it's still intact to a degree.

  Analyzing the water was partly to check for that.

  Sure enough, the water that got here had a similar composition with the 『Aegis State Waterworks Network』.

  Supplying a large amount of such clean water like this is impossible in the current age.

  『No no, even in general, this is terrifying…』


  『This magic could ruin a country depending on how you use it…』


  『I can do that if I want to but there's no point in doing so… So yeah, the places where they mix in the poison should be around here.』


  I draw two circles on the map.

  Both are near the cores of the waterworks called, 『Sources』.

  The source of all water in the network is called 『Great Headwater Orb』, it's a type of large-scale magic tool.

  There are around 20 of these 『Sources』 in the waterworks, and these two are of particular large scale.

  They're called 『The First Source』 and 『The Sixth Source』 respectively.

  『Topmost upstream… There the poison…』


  『If there's only two, then we only need to go take a look at them in turn! …Where'd we go?』


  『This one has a high probability of being correct.』


  I point at the 『The Sixth Source』.

  『Aegist State Waterworks Network』 is a product of ancient ruins.

  Since the waterworks were underground and built really sturdily, it managed to withstand the Mana Fusion Reactors explosions and survived until the present days… but 『The First Source』 was situated close to a Mana Fusion Reactor.

  If one of them still remains today, it would be The Sixth Source

  The demons should have enough life force to move that many dolls by gathering life forces from places where water from The Sixth Source flow to.

  『Got it!』


  『Let's hurry up before there's more victims!』


  We push our way into the highways while talking.

  …Oh right, before that.

  『Let's drink this water.』


  I put water from the empire's waterworks into three cups and present them to the girls.

  I also prepared my own cup and drank it all at once.

  Ruli and Alma looked like they couldn't believe what they just saw.