[greedyspectator]

@Zero
Well, assuming IS cores are basically fusion reactors with an AI attached, the nanomachines probably got the energy from that. It needs a hell lot of energy, to the point that I'm honestly confused why such exotic abilities get used the first place. It's more practical to reroute all that damn energy into a laser or a railgun. But it's possible.

The nanomachines probably get their energy wirelessly from the IS. This can be done with technology today, but just not in any practical efficiency, but since IS verse is far more advanced than RL, this is actually quite reasonable. Then, the nanomachines are probably controlled by a program inside the IS. It's impossible to compress too much processing power into nanomachines due to physical constraints. It's also impossible for the nanomachines to get sensory input from anything but the IS commands, since sensors that small rapidly degrades in high speeds. Therefore, the nanomachines itself only receive instructions from the IS using sensory input (temperature, enemy location, etc) from the IS itself. The nanomachines probably have small molecular webs to carry water droplets in the air, similar to what some plants actually have. They probably move via an electromagnetic field created by the IS. Since the nanomachines are magnetic but water is ferromagnetic, the nanomachines constantly gets attracted into the IS but the water constantly gets repelled. Adjusting the energy pumped into the electromagnetic field allows the nanomachines to be quickly moved around along with the water. This is probably how all the tricks Tatenashi shows is done.

Note I always use probably, here. Making water move in midair like magic is a problem far above my pay grade.