(Answered) Mechanized battle armor on units with unusual movement modes

[A. Lurker]

Clarification, please: per this recent thread, vehicles carrying mechanized battle armor cannot expend jumping, VTOL, or WiGE MP while doing so. I have a few attendant questions:

1.) Does that rule cover 'Mechs as well, or can a 'Mech carrying battle armor in this fashion still jump?

2.) Can a unit carrying mechanized battle armor expend underwater MP (via UMUs or simply by virtue of being a submarine), and are there any special conditions attached (such as the battle armor itself needing to be capable of underwater operation)?

3.) And finally for completeness' sake -- apologies if there's already an earlier ruling I simply don't recall at the moment --, what happens to battle armor carried by a 'Mech that suddenly enters water of depth 2 or greater? (I'm assuming here that battle armor can "ride" 'Mechs in depth 1 water and naval surface vehicles just fine as long as their ride isn't destroyed and the location they occupy stays "dry" amd basically asking about sudden submersion; please correct me if that base assumption should be incorrect, though.)

[Xotl]

As for your first question, the ruling specifically mentions vehicles twice: it does not apply to mechs.

I'll check on the rest.  Thanks.

[A. Lurker]

Looking forward to it, and likewise thanks; both for the first answer and in advance. :)

[Xotl]

No UMU either.

Still working on the depth thing.

[Xotl]

All full-sized battle armour, PA(L)s, and environmentally sealed exoskeletons are capable of surviving underwater at depth 2+.  UMU capability isn't a necessity, although it does allow them to move by themselves; without UMU capability, any suit that falls or drops off a Mech underwater will be unable to move in TW scenario terms, as per TW pp. 56-57.

New TO errata will clarify this more exactly:

④ Extreme Depths (p. 43)
Before “IndustrialMechs”, insert the following new subsection:

     Battle Armor: The only battle armor suits that can survive past depth 15 are those with UMU MP. Battle armor units lacking UMU are instantly destroyed if they descend deeper than depth 15.

[A. Lurker]

So let me see if I understand this correctly.

1.) Vehicles carrying mechanized battle armor cannot expend jump, VTOL, WiGE, or UMU MP while so encumbered. (I'm actually a bit unsure whether the last case can ever apply, since submarines technically have no need for UMUs and other vehicles can't mount them as far as I'm aware; thus it's not quite clear yet how much specifically subs suffer from this restriction.)

2.) 'Mechs, however, can do all these things, including using UMU movement while carrying battle armor.

3.) Mechanized battle armor other than unsealed exoskeletons on a 'Mech (and possibly the outside of a submarine, depending) can survive underwater just fine and will be able to act normally once back above the surface, but if they're not equipped with UMUs themselves, then (a) dropping off will leave them stuck in place (at whatever depth they were, too, or do they sink?) -- though potentially still able to act from there, especially if armed with energy weapons, and likewise potentially still able to be picked up later -- and (b) diving deeper than depth 15 (not a concern on most maps, but could happen) will destroy them.

Do I have that about right?

[Xotl]

Rather than explaining it, if you don't mind being a guinea pig I'll place all the relevant errata in one place and let you tell me if you think it's clear.

② Underwater Movement (Non-Naval Units) (TW p. 57)
After “Prohibited Units”, insert the following new subsection:

     Mechanized Battle Armor: While battle armor lacking UMU are immobilized if submerged, they can still be transported by other units when submerged as per the normal rules (see p. 227).

② Mechanized Battle Armor (TW p. 227)
Under “Magnetic Clamps”

Mechanized battle armor units equipped with magnetic clamps can mount standard ’Mechs and vehicles (except for VTOLs)
Change to:
Mechanized battle armor units equipped with magnetic clamps can mount standard ’Mechs and vehicles (with special movement restrictions listed below)

② Mechanized Battle Armor (TW p. 227)
In between the “Magnetic Clamps” and “MP Reduction” subsections, insert the following new subsection:

     Movement Restrictions: Whether or not the battle armor is equipped with magnetic clamps, no vehicle may expend UMU, VTOL, WiGE or Jumping MP while carrying mechanized battle armor, and no ’Mech may expend UMU MP.

④ Extreme Depths (TO p. 43)
Before “IndustrialMechs”, insert the following new subsection:

     Battle Armor: The only battle armor suits that can survive past depth 15 are those with UMU MP. Battle armor units lacking UMU are instantly destroyed if they descend deeper than depth 15.

[A. Lurker]

Could still use some clarification of what depth dropped battle armor are immobilized at if and when that happens, I think -- do they keep floating exactly where they were (which for those shaken loose from a 'Mech would presumably be the previous depth of the upper body, wherever that was at the time), rise to the surface, or sink to the bottom? Also, if they're "immobilized", does that mean that they formally count as immobile targets or merely that they effectively have 0 MP?

Regarding submarines vs. UMUs, re-reading page 57 makes me feel like I've picking a bit at nits there; it seems reasonably obvious that the two do simply use the same movement mode now. So, neither submarines nor 'Mechs can use "submarine-style" movement while carrying mechanized BA, but 'Mechs can still walk across the bottom normally and a submarine can presumably still carry them along the surface. (That actually raises some side questions about underwater swarm attacks and the target immobilization potential thereof, but I think that's more for another thread since it's no longer simply about mechanized battle armor transport.)

I'm also assuming that non-UMU battle armor can't just voluntarily abandon their ride underwater since as per page 214 they wouldn't be allowed to enter the water hex on their own initiative anyway, so all this pondering about "stranded" battle armor mostly covers units shaken loose by a target they were swarming entering water or stuck in place by the sudden destruction of their carrier.

[Xotl]

We'll tweak the wording a bit more then.

② Underwater Movement (Non-Naval Units) (p. 57)
After “Prohibited Units”, insert the following new subsection:

     Mechanized Battle Armor: While battle armor lacking UMU cannot enter water of depth 1 or greater, they can still be moved into and underwater by other units as per the normal rules (see p. 227). Mechanized battle armor being transported in such a fashion cannot voluntarily abandon their transport; if forcibly removed or their transport is destroyed, they immediately sink to the bottom of the hex and are rendered immobile.

[A. Lurker]

I think that works. From a "simulation" point of view, the BA dropping potentially from the water hex's surface right to crush depth in a single turn may sound a bit odd, but at some point ease of game play has to take precedence.

Also, I'd definitely read this as attacks from underwater sources against stranded battle armor getting the -4 "immobile target" bonus (of course, if they were by chance equipped with a weapon that worked underwater and the attacker was in range, they could shoot back; could probably even still launch leg and swarm attacks against somebody reckless enough to move into their hex along the bottom, too). If that's the intent, I think we're clear.

[Xotl]

The use of immobile is very deliberate: yes, the -4 would apply.  As such, no leg/swarm attacks would be possible, though they could fire I suppose.

[A. Lurker]

*nod* The prohibition against anti-'Mech attacks is probably worth spelling out then, too, just in case. And yes, at least the usual suspects among energy weapons should probably still be usable (although I'm not sure off the top of my head about any "pure infantry" ones troopers with armored gloves or anti-personnel mounts might optionally carry in place of their default auto-rifle; we don't have underwater ranges for those, IIRC, so it may be that they just plain don't work there).