"Oh! Yes, you should talk to the engineers at the laser." He gestures out towards the shore, where a twenty-metre-tall pointy thing can be discerned.

He goes towards the twenty-meter-tall pointy thing. Looks for engineers.

There are engineers swarming it!

Any who don't look super busy right now, or who look less busy than the others? Ones he could possibly interrupt?

No, not really, all of them look pretty busy.

Sigh.

He'll drop on one and– "Hi! I have the magical ability to change materials, not including magical ones, is there any chance I can help out somehow and I do apologize for the interruption."

The woman stops and looks at him. "Materials? Like what?"

"Like I can do a bunch of metals just fine and so long as I know what I'm making and it's non-magical I can probably do it just fine?"

"We don't need new materials, we need to get the machina finished up and charged in time!"

"What do you need to get the machina finished? If you need bits of metal reshaped I can do that, if you need them melted or solidified quicker I can do that, if you need me to turn it from whatever metal it is into some other metal so it's stronger I can do that, if you need me to cool down the surrounding area or something I can also do that."

"—you can affect temperatures? Can you make whatever kind of energy this machine uses?"

"Depends on what energy it uses!" responds Theo. "If it uses steam power then I can help heat up some water, if it uses electricity then– you're probably out of luck on that one if you need me to send it in some specific voltage or charge a battery directly or something."

"We don't know what kind of energy it uses," she confesses. "Still, come with me, you can be useful."

He follows. "Unfortunately I don't know all that much about the components of technology but it's not religiously banned where I'm from."

She starts leading the way but she looks at him over her shoulder, perhaps in envy though it's hard to tell with the goggles and gas mask. "That's very lucky. Where are you from?"

"No idea how it relates to here, but I can be summoned from where I live to the mortal world, and for some reason or another came here this once, having never heard of here or this magic or Sin ever before."

"Not having heard of Sin sounds great," she says vehemently.

They reach a tent near the machina where a chief engineer is giving people orders and receiving reports. The woman informs him of this and explains to him what Theo can do, and he takes Theo to see the battery. It is very old but restored and seems to be completely unlike anything he's ever seen.

"… I'm afraid I have no idea how this battery was made so I'm likely to be of no use with it."

Well. That's a shame. Could he perhaps learn...? If not there are other things he can do to help.

He can learn if they know how it was made! He has a basic idea of how batteries work, at least the ones he's familiar with.

But if they don't, no, unfortunately he has no special information-gathering powers.

They don't really have any idea, all they know is that it produces some form of energy that feeds the giant laser.

So it's probably some kind of electricity but unfortunately he does not have anything handy with which to find out how it's made unless he cares to destroy it carefully. Which, uh, no.

Anything else he can do instead?

Yeah, lots of work, actually, he can help speed it all up by a lot.

He does so. Tries to get information on what they do know about it as he does so.

It was found underwater about a month ago, curated and explored and tested, there were instruction manuals in the computers near it, it's meant to be really powerful.