Ami's mother's condo was a bad place to experiment with bomb-making. It was cramped, well-furnished, and expensively decorated. And even if she found some other space indoors to work, the noise would wake all the neighbors. 'Exercise common sense' was Luna's advice, and common sense said to take her experimentation someplace else.

She wanted someplace private, secluded, far away from prying eyes and listening ears, and hopefully dilapidated enough that breaking things would go unnoticed. Her first thought was an abandoned warehouse, but she didn't expect to find one along Tokyo Bay. Even if they were empty of people, they'd probably have security cameras. She briefly considered renting a space somewhere, but the logistics of such a thing were probably unmanageable, or at least not doable quickly. They could conceivably be called to fight youma in just the next few days, and Ami wanted to be prepared.

Ami was considering parkour routes when she realized that she could just use building rooftops as temporary workspace. They were easily accessible to her, but not to the general public. They had no provisions, but she needed no real tools and no storage space. She could melt and evaporate anything she made to erase evidence of her presence. And if anybody did hear something and decide to investigate, magical parkour would make it easy for her to flee. She could even rotate between different buildings on different nights, if she ever felt that she'd made too much of a ruckus at one spot.

Which might be necessary, since she was going to try to use her magic to make a gun.

Or a gonne, more technically. A primitive hand cannon: A weapon from the days where shooting a firearm meant tapping a torch flame to a touch hole.

The idea was to conjure a barrel from ice, a hollow tube closed on one end. That barrel would be packed with snow and loaded with a bullet, also made of ice, with the snow acting as a propellant. Ami would use her magic to vaporize it into steam, and rely on the gas pressure to expel the bullet out the other end. The barrel would be smoothbore, as a proof of concept, but Ami imagined that she'd eventually be able to rifle them.

It might have been a stretch, but it felt more workable to Ami than the anime from which she'd gotten the idea. Mami Tomoe of Madoka Magica had made rifled muskets out of magical ribbons, which was ludicrous from an engineering standpoint, even if it looked really cool and worked well with her character design.

Ami was giddy. She spent her class time daydreaming about fighting youma, summoning ice gonnes by the dozen, grabbing and firing them one-by-one in in a dance choreography of elaborate flips and spins. Screw being a water Pokémon, she'd be a proper magical girl. She might even dress as 'Ami Tomoe' for Halloween.

That might be tempting fate, though, Ami thought. She remembered that, for all her coolness, Mami Tomoe is tripped up by her own overconfidence and decapitated in Episode 3.

…and for that matter, Madoka Magica also has a different, blue-haired magical girl with quixotic aspirations who dies even more tragically in a later episode. Ami had identified strongly with the fellow bluenette during her first watch, for reasons beyond their shared hair color. Watching that character's death had gutted her.

Ami reflected that Madoka Magica was probably best taken as an example of what not to do after becoming a magical girl.

Oh well. It would turn out differently for herself, Ami resolved. She'd be extra careful.

It was just past two in the morning on the rooftop of a building several miles from the bay, near where Usagi had taken her to practice 'bubble spray'. Ami had texted her mother to say that she was sleeping over at Usagi's house, just in case her mom actually came home from work that day. Then, thinking further, she sent a text to Usagi asking her to claim that Ami was sleeping over, in case her mom called asking where Ami was. That wouldn't do anything if Usagi's mom picked up the phone, but it added some safety margin. Not that Ami's mother would call.

Ami's phone chimed. Usagi was awake. what r u doing?

practicing, Ami replied. She'd almost sent 'practicing my powers', but she didn't want Usagi to have to answer difficult questions if somebody saw her text history. Usagi would understand her meaning.

A chime. not doing anything unsafe r we?

nothing to worry about, Ami typed back, and muted her phone. She'd have to ask Luna if there was a more secure way for them to communicate than by text. She'd forgotten to ask if that was something that the Nintendium supercomputer could do.

Now that she knew to transform into Sailor Mercury first, her experiments in hydrokinesis were proving much easier. Maybe the sailor uniform gave her equipment bonuses to magical ability, like an RPG. That would go a long way towards explaining why they wore miniskirts to fight monsters, beyond just aesthetics.

Anyways, on to magical gunsmithing.

Ami was having little trouble producing ice. But the faster she conjured it, the more amorphous and misshapen the ice would be. That was bad. Even for something like a gonne, which had exactly one moving part, she still needed precision. It would be disastrous if, say, the gonne's barrel got slightly narrower midway down its length. The bullet could get stuck, and then she would be left holding a bomb as it literally exploded in her face.

With some finagling and repositioning of her hands, Ami was eventually able to produce what looked like a uniform cylinder. Next, she'd have to figure out how to make a hollow tube. She tried changing the angle of her hands, tried to will the ice into extruding with an empty center. No luck. She tried conjuring a donut – that was basically a tube, topologically speaking – but didn't have any more success.

The rooftop around her began to look like a collection of failed ice sculptures.

She kept working till the sunrise.