Mindless

:see also nonsentient, same idea but a term used in basic set
==house rules==
a 2017 thread http://forums.sjgames.com/showthread.php?p=2120543 points out, PK suggested at http://www.mygurps.com/a_allies.html?p=ia&v=0 to replace IQ-10 [-200] with what RyanW calls Mindless (0)
that URL is down but here is archive https://web.archive.org/web/20150919203707/http://www.mygurps.com/a_allies.html?p=ia&v=0
this was called "Non-Sentient Allies on the Cheap". Supposedly the balance is "complete immunity to mind control, possession, etc."
The vagueness of this raises questions, since the highest any individual immunity can provide is 30 points, meaning the 2 explicit examples are only worth 60.
To help, whswhs suggested this also include immunity to pain (worth 30 points) bringing the total to 90.
Other natural candidates would be B60 indomitable (15) and B95 Unfazeable (15) for another 30, bringing the total to 120.
Vehicles would also usually have something like Doesn't Breathe (B49) for 10.
Plus: something like Unfazeable makes it impossible to take discounts like a dozen phobias, which can ultimately be way cheaper than buying down IQ.
Pudding did a followup at http://papermenplasticmonster.blogspot.com/2016/10/nonsentient-allies.html?
The thing is that to be useful, vehicles usually have to buy a lot of other stuff like Payload and Controls not to mention enough ST to transport passengers. The discount from IQ helps to make that feasible.
==no purely mental traits==
The downside of IQ 0 is the inability to take mental advantages, but that also means no purely mental disadvantages, which can help to lower point value.
The fact is though that IQ 0's inability to act probably counts like all kinds of mental disadvantages (nearly infinite) but also effectively a bunch of advantages, which in theory balance out. An IQ 1 thing would lack many of these benefits, and since it CAN take mental traits, would be able to save points that way in theory to buy them if they wanted.
This "tier" difference between 0 and 1 (sentience) also exists between 5 and 6 (sapience) where a bunch of benefits like 'can learn language' and so forth are balanced by shifting from animal-control magic to standard mind control magic. Or empathy v animal empathy.
==Mindless, Not Brainless==
Z6 covers this, though the choice of name could cause some confusion with the No Brain advantage. In this case it's the metaphorical 'brain' one has, not a literal one.
It explains:
:here, “mindless” means that zombie “racial” templates drastically penalize IQ (racial IQ modifier of -2 or worse); restrain or remove free will via Reprogrammable (p. B150), Slave Mentality (p. B154), or Automaton (p. B263); and/or impose disadvantages
consistent with animalistic behavior, like Bestial (p. B124).
Note: Automaton is a -85 metatrait including
:Hidebound [-5];
:Incurious (6) [-10];
:Low Empathy [-20];
:No Sense of Humor [-10];
:and Slave Mentality [-40]
Since it includes an already mentioned disadvantage, the removal of free will is probably just referring to those two, and not the other aspects (H/I/LE/NSOH)
Z69 explores this with new metatraits like Inexorable and Legally Dead
category:0-point meta-traits