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Death March to the Parallel World Rhapsody

Chapter 213: Preparation for Elimination 🔪

Published: September 9, 2025

September 6th: Some additions and revisions made.

February 11th: Typo corrections made.

This is Satou. I've heard the saying, "If you dilute poison, it becomes medicine," but I don't think that's always true. The reverse—"even medicine can become poison if too concentrated"—seems to apply in most cases. In everything, "too much is as bad as too little."

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"Hello, Mr. Satou."

"Ah, Lady Lua, perfect timing."

I handed over about five large bottles filled with freshly made "sleeping medicine" for the jellyfish to Lua. She carries the same kind of magical bag, the "magical bag 'holding bag'," as I do, so she can easily carry heavy loads without trouble.

For the past ten days or so, I've been giving three to five types of sleeping medicine daily to Lady Jia for testing. So far, the most effective one uses the sap from the World Tree.

"I have indeed received them. I believe you've heard the experimental results through the 'telephone' from Lady Aze, but here is the written report from Jia."

I thanked her and took the stack of papers from Lua.

It seems the weaker ones wear off in about ten minutes, but those that are too strong nearly induced death-like states, even stopping vital signs, which was quite serious.

Since it would probably be fatal if used on humans, I've been borrowing an unmanned workshop outside the city to mix these medicines. Apparently, this was previously used by Spriggan Mr. Rereck.

There seems to be a small magical spring beneath this mansion, so the magical artifacts here run without need for magic power recharging, which is quite convenient.

It's so convenient that it tempts me to become a recluse, but if I stay out late, Arisa calls me every hour on the 'telephone' to check in, so I can't relax too much. Lately, she's been putting Pochi and Tama on the phone to induce guilt—quite a sophisticated tactic. I asked how she managed that since it shouldn't be possible on a normal telephone, and she replied with a smug face, "I worked hard to improve it."

Well then, having handed over today's quota of sleeping medicine, it's time to move on to other tasks.

I'm currently working on four projects involving sleeping medicine.

The first is the creation of sleeping medicine for the jellyfish.

Since few practitioners can imprison jellyfish with spatial magic cages, we're testing whether combining ice cages with sleeping medicine can compensate for the lack of casters. Three days ago, a test with a particularly effective sleeping medicine showed results—apparently, some jellyfish are still asleep. If it lasts for about ten days, we can give the green light for the jellyfish cage tactics.

The second is considering measures to prevent jellyfish resurgence.

For this, I'm thinking of autonomous interceptor satellites. Imagine artificial satellites for base defense. It seems that as long as mana continues to be supplied, the cube shape can be maintained even in the void, so I plan to use this for altitude maintenance. The biggest problem is magic power consumption. I also want to add laser turrets and an operating brain to make floating turret golems.

Here again, the main issue is the power reactor. I want to build a system requiring minimal manpower, so like the power reactors of the Living Dolls, I intend to use the Philosopher's Stone. Actually, Sotolineya-san has already lent me three power reactors from Living Dolls. She warned me sternly, "Don't break them," so reckless experiments are tough to carry out.

With magic, nuclear fusion should be possible, but I have no materials to know where to start. That will be a future challenge.

The third is controlling the aerodynamic engine.

I combined the knowledge of building control devices I learned making Living Dolls at Sotolineya-san's place and my programming skills.

Recently, I've been trying a mechanism I heard in the Duke's Capital: rotating to average out output fluctuations. There are cranes and large fixed stands in the mansion's basement, so such work advances smoothly.

The control mechanism is perfect, but the response speed of information is insufficient, and control of the aerodynamic engine can't keep up. It looks like it'll take a bit longer to complete.