by gusindor » Mon Mar 31, 2014 6:03 pm
For those who don't know: Frames operating in hostile environments, such as space, underwater, extreme temperatures etc. only get one white die. However, they can have equipment that lets them have two white dice as per normal. Environmental equipment (someone should give it a cooler name) acts just like any other system, taking up one of a frame's four slots and getting disabled by damage.
I forget whether this is in the rulebook or just a popular house-rule. What counts as a "hostile environment" is open to some interpretation, but space and water are generally accepted. Deserts, marshlands, tundra, volcanoes, high- or low-gravity planets, inclement weather, vertical surfaces (can you imagine a battle on the side of a cliff?) radiation, and other weirdness are also possible.
Anyway, to me that seems to imply that mobile frames can work just fine in at least some amount of water, but most of them aren't very graceful swimmers. No idea how deep they can go, but I imagine most frames are tough enough to withstand pressures that would be harmful to humans.
In all this, I am assuming the pilots have enough air, and any tech that would jam or short out is properly sealed. Either of these could be your environment system, or you could decide as a group that they're ubiquitous enough to not count.
Based on my limited understanding of how light behaves in water, it seems like laser-based weapons would function, but there would be some difference in the way the beam travels that takes some getting used to. Something about refraction that a veteran knows how to compensate for, but throws off a rookie's aim.
Physical weapons might be a bit slower or less precise if they weren't designed to move through water, but in principle they'd work just the same.
I have no idea how plasma behaves in water.
There are substances that burn just fine underwater, so fire is still technically an option. Heat might be a concern, I'm not sure. I don't know what effects boiling the water around you would have, or what could cause that, but I know it wouldn't be pleasant.
Similarly, electric, cryogenic, or corrosive weapons would probably not work as intended, although if used properly they could be devastating. Weapons that use fluids, like an acid gun, glue gun, flamethrower (whether they shoot burning gas or liquid), or whatever else you invent, would need to take into account all sorts of complicated physics. Magnetic, vibration and other weapons that don't actually shoot anything would probably work just fine.
Always bring a speech to a gunfight.