Alternate Ability + Compartmentalized Mind

[CeeDub]

Salutations!

Alternate Abilities usually take a Ready maneuver to switch between "modes". What if the character has Compartmentalized Mind? Can he or she then use both abilities in different modes? I'd assume that it would still take each mind a ready maneuver to switch, but could one "mind" have setting A and the other setting B, so both could be used at the same time?

Of course, this would only work with mental abilities. Goes without saying.

[Mathulhu]

I don't think so.

If a character has ability A for 50 points and has bought ability B for 50/5=10 points. They have bought the potential to have ability B.
At the beginning they have A active and B inactive, they effectively don't have B.
When they switch from A to B they effectively don't have A.

So with compartmentalised mind on one turn you could use A twice or B twice or use A once then swap to B or vice versa.

[Anaraxes]

You can use more than one ability at a time from a set of AAs by paying {incorrect cost deleted; see PK's reply below}.

I could see a generous GM deciding that CM had independent "settings" per mind, but I don't think that's intended.

[PK]

Part of the discount of an AA is that you can only use one mode of it at a time. Period. Compartmentalized Mind does not change that. (It's worth noting that Altered Time Rate does, because your ATR turns are consecutive, not concurrent.)

So if you have Pyrokinesis 3 and TK Grab 4 as AAs, plus CM 1, you can do one of the following:

1) Burn two people (or one person twice).
2) Lift two things with BL 3.2 (or combine your BLs to 6.4 to lift one heavier thing).
3) Do something non-psi while burning one person.
4) Do something non-psi while lifting something (with BL 3.2).

(It's worth noting that we've let a few things slip by that didn't follow this rule, but it is the correct rule. Where possible, we've errata'd or clarified them.)

If you want to be able to use more than one "slot" of your AA at once, see GURPS Power-Ups 8: Limitations for the full expanded AA rules. (Short version: Pay full price for the most expensive X abilities and then 1/5 cost for the rest, and you can have X abilities available or "on" at once.) If you wanted a character with CM whose minds only had access to different abilities, use the rules I just gave you to ensure that you have access to enough of them, and then limit CM with "Accessibility, Cannot use multiple 'copies' of the same AA ability" (-10%).

[PK]

Originally Posted by Anaraxes

You can use more than one ability at a time from a set of AAs by paying the 1/5 cost multiple times. That is, to use two different abilities at once, you'd pay 2/5 cost of all but the most expensive.

Close, but you're inverting it. To use two different abilities at once, you pay full price for the most expensive two, then 1/5 cost for all of the others.

[Anaraxes]

Originally Posted by PK

Close, but you're inverting it.

Thanks for the correction. I knew I should have looked it up!