A/N: Beta'd by Bob Saget. Finally getting some mileage out of my engineering degree.

Just to clarify, I re-ordered a couple chapters so that everything is in nicely chronological order now, and the chapter before this one gained a couple paragraphs on the sealing teacher near the end of the Personal Log. As a result of this will have told you I updated 3 chapters at once or something similar, but it's just the one and a bit.

ooo

Personal Log - year 12 month 9

There was a little voice in the back of my mind, telling me that my first mission would be a disaster. Our client would be attacked by missing nin, his family would get captured by samurai, the road would be mined and we'd get swarmed with our backs to a cliff by bandits led by a woman with sharpened teeth. It wasn't, looking back, a particularly logical fear but I couldn't shake the feeling that some unknown force would conspire to make my first mission hell. Imagine my surprise when on our first escort mission, nothing happened. Not in the first mission, not in the second, not in the third. We met a person or caravan, we conveyed them safely to a place, we got paid, we went home.

I suppose it's another slight piece of evidence on the pile in favour of this world being deterministic as opposed to fate-based. Right next to Hinata's kid brother and Naruto not learning Shadow Clones.

ooo

With the recent windfall of cash, Tetsuo caught himself humming a tune as he hopped from roof to roof in the bright sunlight. I'm happy, I'm feeling glad, I got sunshine in a bag, went the accompanying lyrics in his head. I'm useless, but not for long. The future, is coming on. It's coming on. He hadn't spent the time to migrate over every detail about his previous life to his new meaty hardware, nor every bit of pop culture, but a number of songs had made the jump encoded as contextual information in the background of other memories. And he'd had to do a lot of digging through past memories recently.

Some people said money was the root of all evil. He didn't really agree - to him it seemed more like a medium of exchange that could under certain circumstances be traded for power. He wasn't really in a position to argue though, considering he was using his most recent influx of liquid assets from missions to create better ways of exploding people.

Tetsuo sighed. He couldn't sing the songs out loud like he wished to. Couldn't murmur lyrics from a non-existent language and culture under his breath where the workers could hear. A certain amount of allowance could be made for child geniuses being weird, but that likely didn't extend to composing dozens of songs in a fictional language, most in completely different styles that no-one had ever heard. Especially while also "inventing" entire new categories of cuisine, creating brand new weapons for the ninja armies and spending an excessive amount of time training.

Every extra impossible thing he did was extra strain on the minds of the people reading his cover story, and the scrutiny would only increase as he got older and lost what little presumption of innocence he'd had. Who knew where the line was, that would make them take a step back and consider alternate explanations? They didn't have to get the right answer about what he was, they just had to start asking where he was getting his ideas from. He certainly didn't have the spare time to figure them out conventionally.

Did he have contacts abroad? Was he talking to Konoha's enemies? What was he trading for all of this information? Was he selling secrets? Was there some unknown country that was writing all this music and inventing these recipes and creating these weapons? Were they a threat? These were the kinds of questions he couldn't afford to have asked, because he couldn't give information that would set them to rest. If he claimed that he was from another world they were more likely to believe he'd been fooled by a genjutsu or a Sasori style mind control seal than they were to believe him. It would hang over his head forever. Denying him access to the best training, the juiciest techniques, the most interesting secrets.

He arrived shortly at the wide open courtyard of a foundry, with smoke belching from a large chimney. He entered through wide open doors to a scene from the centre of the earth. Large crucibles of glowing molten metal were lifted and carefully poured into wide clay beds to form bright gold ingots.

A large, hairy man in black coveralls and a leather apron came over as soon as he noticed the small ninja, his skin glistening in the heat and light. His beard bristled, his eyebrows beetled, and his belly stretched at his clothing, yearning for freedom.

"You brought the moulds?" He asked in a gruff voice with a slightly deferential tone which still sounded odd to Tetsuo's ears. It's still strange to be part of the ruling caste, Tetsuo mused. Ever since I got my forehead protector it seems that my apparent status has risen. Before I could have been a normal child, but now I am unmistakably ninja and it seems that has an effect. Ah well, it's hardly an issue to get some modicum of respect, even if it seems to be less than it would be due to my age.

"I did," Tetsuo confirmed, unsealing ten clay cylinders - five large, five small - in a crate as the two moved from the main foundry to a smaller room. Hollow castings made from a wooden positive that he'd made sure to carve out in full view of his team mates and teacher.

"Are you sure I can't look at them first?" The man asked. "There's more to this than just plonking in whatever shape you want you know, and any kind of weapon will just shatter in combat if it's from a rough casting like this."

"I am aware, Toriume-san," Tetsuo replied, unconcerned as he set out the cylinders in a trough of sand while a worker connected them to a single channel of ceramic, then busied himself fetching a small crucible of iron at the end of a long pole. "In fact, I'm counting on it." Your metallurgy expertise is noted, Tetuso continued in his head. You're a decent guy, I'm sure. If any normal 12 year old came in here and tried to get you to do something like this you'd be perfectly right to question their competency. The fact of the matter though, is that I have information that you do not. Specifically, engineering techniques created and honed by another civilisation over hundreds of millions of man-hours on another world. I've set up the sprues and the overfill reservoirs, the air has space to escape and I don't need perfection here anyway. Brittle iron is fine. Even with defects it'll do the job, and secrecy is so very necessary.

The man grunted, not happy but unwilling to push it. A young ninja could get away with so very much if the mood struck him. "Pour!" He ground out.

With practised ease the worker sent an even stream of molten metal into the centre of the arrangement, which flowed outwards along the paths dug for it into the tops of the cylinders, where it disappeared into the waiting moulds. Tetsuo's eyes were like pools of bright amber with reflected light as he stared hungrily at the cooling metal.

They stood for a time, as the glow went from bright gold, to cherry red, then dull crimson at the core as the edges started to fade to black. Eventually Toriume grabbed a long-handled pair of tongs and grasped the centre of the work. With a grunt and a heave the connected cylinders came free of the sand and were quenched in a trough of water. They bubbled and boiled and frothed as the casts cracked, then violently disintegrated under the pressures of the temperature change. A loud crack filled the air as the metal came free, though still hidden in the murk.

"My thanks, Torume-san." Tetsuo bowed his head slightly as he brought out his wallet. "Now, as per our agreement?"

"Yeah, yeah, I'll leave you alone," he conceded with bad grace, taking the money and leaving the room, closing the door behind him.

Well then, let's see what we've got, Tetsuo thought as he pulled the still connected metal structure from the trough. It looked like nothing so much as a hideously mutated metal spider with each leg splitting apart into two, then linking back together in club feet. One by one he broke free the metal shapes from the solid sprues where metal had flowed into them. On the nearby table he laid out the fruits of his labours: five rather strange looking kunai, each in two pieces. The hollow body that would hold the explosives, and the standard handle with a threaded base ready to be screwed into the top.

Imagine the ridged pineapple shape of the most famous style of grenade. Now picture a vicious spike on one end and a ring-end kunai handle on the other and you'll have a good of what Tetsuo held in his hand. He carefully inspected them for defects, tapping them one by one with a piece of metal; They rang with a high, sharp ting.

ting.

ting.

ting.

tnk.

Tetsuo frowned and held up the last grenade body, carefully going over every section without finding any visible or tactile flaws.

Hmmm, maybe it's internal? If I make a loop of chakra coming out of my hand and back in, weak enough to pass through metal, then I should be able to feel any differences in density between this and the others. Like a poor man's magnetic inspection device, except using alien space magic instead of magnets.

His hand began to glow as he passed it over first one grenade body, then the other. Yep, definitely something funky in there. Best not use that one. Ah well, four out of five isn't bad for a first try. I can cool them slower next time.

Then it hit him, it was done. He grinned savagely as he looked down at his prize. Oh these things are going to be so... very... useful.