The Steel Roach That Raises Blood Pressure

What kind of robot was the fourth opponent that made Naru scream when she still hadn’t adapted to having a woman’s body? “Steel Roach…?! Is this going to sell a ton of hypertension meds? Or is it being marketed as a low-blood-pressure remedy?” A few pharmaceutical companies were among the tournament sponsors.

“Naru, no matter how tough the Steel Roach is, the V-Killer should still be able to beat it, right?”

“You know exactly what happens once it drags the fight into a mud match, Cheong-bi.”

No one could ever guarantee victory or defeat in a mud fight. That truth applied not only to sports but to every contest in this world.

“So in a mud fight, you really can’t tell who’ll win?”

“Exactly.”

“Then just become a high-performance tank that can climb right out of the mud~!”

“That’s true. But that cockroach-looking thing has defense exactly as nasty as its appearance…”

The Steel Roach. From the name alone it was the Steel Cockroach. If you had to describe its appearance in a single sentence, it would be this: a giant cockroach robot. ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠Six servo-driven legs let it scuttle forward or sideways, letting it walk exactly like the real thing.

The real blood-pressure-raising part started here.

“You know the rule that relaxes weight limits for walking robots, right?”

“They’re hard to build and slow, so the bonus is only fair.”

Walking battle robots received a relaxed weight cap. The first type—wind-up-toy style—could reach 1.5 times normal weight. The second—true animal-style locomotion—could reach twice normal weight. The Steel Roach used the second method. In the 110 kg class, that gave it a staggering 220 kg total.

“But the weight limit on weapons stays exactly the same.”

“Safety regulations, obviously.”

The extra weight of the complex drive system had to come from somewhere. Whatever remained after subtracting the drivetrain and weapon went straight into armor. The result was a machine that was insanely, almost unfairly tough. Its defense matched its cockroach appearance perfectly. One match proved it: for a full three minutes it did absolutely nothing yet never suffered a KO.

“If the Active Weapon Rule didn’t exist, it would be even tougher.”

“I heard ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠the educational-broadcast tournament we watched as babies failed because it didn’t have that rule.”

Still, regulations required at least one effective active weapon. That was why the Steel Roach carried a single lift—enough to flip an opponent or shove it out of the arena. Since the weapon itself wasn’t heavy, the armor stayed almost completely intact.

(Maybe I should listen to ASMR after the match… my blood pressure’s already climbing.)

Battle-robot tournaments naturally banned electronic devices in the arena. That was obvious, but the sport added one extra clause: the device must not be used for robot control. Without that wording, control itself would become impossible.

(The V-Killer’s weakness is its underside, but… the opponent’s a defender, so it should be fine.)

The V-Killer was extremely vulnerable to vertical spinners. Its chassis told the story. The front formed a sharp V-shape. The rear was rectangular with the corners shaved off—a stylistic choice to make the design more interesting. Every surface used steep sloped armor, including the completely smooth underside. It looked as sleek and thin as a stealth fighter. Horizontal spinners that struck sideways were easily deflected, but vertical spinners attacking from below found a fatal flaw.

(It’s a one-piece carbon structure, so I can’t swap armor panels…)

Some robots could at least change the bottom plate to vertical armor, but the V-Killer’s integrated carbon-fiber monocoque made that impossible. Abrasion-resistant steel armor wrapped around the chassis like a belt.

(I sacrificed attack range for faster acceleration. How will that choice hold up against the Steel Roach?)

The weapon sat underneath the robot, reminiscent of a lawnmower. This configuration was called an undercutter. A wide, flat horizontal spinning blade—properly called a blade from here on—extended beneath the chassis. Compared with other horizontal spinners, it had a unique trait: short but extremely thick. The trade-off was a narrower attack arc, but it reached maximum RPM much faster.

Large wheels provided quick movement. Bigger wheels meant higher speed; that was common sense. The drawback was higher power draw, but the V-Killer’s powerful drive motors handled it without issue.

Those big wheels also gave the slim chassis surprisingly high ground clearance. Smooth sloped armor combined with that height created terrible synergy. The underside became an easily exploited weakness.

V-Killer versus Steel Roach. Match start.

(It looks like a cockroach and is as tenacious as one, but at least it isn’t fast. That’s a relief.)

Legs being faster than wheels was no easy feat. How many land animals broke 100 km/h? How many vehicles did? The numbers weren’t even close.

(Is the controller too big, or are a woman’s hands just that small?)

In Moon Naru’s now-feminine hands, her old controller felt oversized. The explosive mobility she had mastered as a boy now slipped from her smaller grip.

The V-Killer opened the match by slamming into the ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠wall three times. It looked like a total newbie trying to drive an S-class car on day one of a racing game.

(Ugh, my blood pressure’s already rising… and it’s my own fault…)

Moon Naru’s blood pressure climbed from the very first second. Meanwhile the Steel Roach had done nothing at all. While the V-Killer rammed itself into walls, the walker simply trudged forward, slowly making its way toward the center of the arena.

(Okay, I can catch it like this. Yes—the legs!)

After a brief moment of panic, Naru found a grip that fit her smaller hands. The V-Killer dove under the Steel Roach and sliced off one leg in a clean arc that looked like a scythe cutting through reeds.

(This is the power of the undercutter!)

The greatest advantage of an undercutter was how easily it could target an opponent’s underside.

(Ah, but no insect stops moving after losing just one leg!)

Arthropods could lose one or two legs and keep going. The Steel Roach was no different; it had copied a cockroach’s structure almost perfectly. Even a tailless whip scorpion could still move with four of its eight legs missing.

(Ah, the underside!! This feels weirdly embarrassing to watch…)

The V-Killer exposed its own underside and was promptly lifted. The scene resembled a subway pervert flipping up a woman’s miniskirt. The comparison felt awkward, but since they were only robots, no one needed to care.

The Steel Roach began trudging toward the out-of-bounds zone. Legs made it slower than wheeled machines.

(That’s why you don’t use big wheels for nothing~!)

While the Steel Roach lumbered along, the V-Killer slipped free like a snake sliding over a wall, thanks to the enormous torque from its giant wheels. It looked like an off-road SUV escaping a swamp. At the same moment it slammed into the Steel Roach’s side.

“Kyaaaaaaaaaaa!!! This is it!!!”

(There’s the pterodactyl scream again…)

What happened next was spectacular.

The Steel Roach that took the hit floated upward, spinning like a tornado. It was sucked into the out-of-bounds zone as if disappearing down a toilet drain. The out-of-bounds count began. The arena fence was tall enough that escape was nearly impossible.

“10! 9! 8! 7! 6! 5! 4! 3! 2! 1! Steel Roach out-of-bounds defeat! V-Killer wins!”

0:40. The entire match was short enough to fit inside a single ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠Shorts video. Even so, it counted as a long fight for the V-Killer. Its previous three matches had ended in under twenty seconds.

The Steel Roach had indeed tried to force a mud fight, but the V-Killer proved to be a high-performance tank. It escaped the mire with ease.

The V-Killer’s record now stood at three wins and one loss—a strong enough tally to reach the tournament under normal circumstances.

“Naru, you won. An out-of-bounds victory before your blood pressure could climb any higher.”

“It was a lucky hit.”

“Luck is a skill too.”

That single strike—lifting the Steel Roach, spinning it like a tornado, and dumping it out of the arena—had decided everything. Without it, victory would have been far from certain.

“Tournament qualification… wait, why does the ranking table look like this?”

Naru sensed something strange on the leaderboard. What on earth was going on?