I have a problem with the correct interpretation of Stunned state (page 257), most notably with the following sentence:

In addition, Stunned characters cannot take Actions or Reactions such as Evasion .

I had a very long and heated discussion with our local GM on the topic last night. I thought that this means that being Stunned you cannot make any Actions or Reactions of any kind. He claims that because Evasion is explicitly listed, that it only applies to Actions and Reactions that are like Evasion, i e, that a character could still use a Reaction to, for instance, attack with a Servo Arm, or use an Action to Focus Power (since it is not a physical 'motion', but rather just a concentration).

Which one of these interpretations is more accurate?

Yours is pretty much correct and your GM is wrong. It says quite clearly "cannot take any actions or reactions" and that the mention to evasion is purely an example for those who don't know what a reaction is. Basically anything which counts as action or reaction is nullified and you cannot use it. I don't see the logic to it either, if you are stunned you cannot really focus on anything at all.

I'd side with you on this one but if your GM disagrees then unfortunately the GM has to be obeyed (wrong though he may be).

I concur with Calgor.

Yours is pretty much correct and your GM is wrong. It says quite clearly "cannot take any actions or reactions" and that the mention to evasion is purely an example for those who don't know what a reaction is. Basically anything which counts as action or reaction is nullified and you cannot use it. I don't see the logic to it either, if you are stunned you cannot really focus on anything at all.

I'd side with you on this one but if your GM disagrees then unfortunately the GM has to be obeyed (wrong though he may be).

Yep. As Calgor says, the Rules As Written and the Rules As Intended are with you.

However, the GM has Rule Zero with him. Rule Zero > RAW and RAI.

I could maybe see a situational case for purely mental actions* if the source was described as being paralytic but was using the Stun rule mechanics.

*Stuff you could fob off onto the other half of a Rite of Duplessence.

Yours is pretty much correct and your GM is wrong. It says quite clearly "cannot take any actions or reactions" and that the mention to evasion is purely an example for those who don't know what a reaction is. Basically anything which counts as action or reaction is nullified and you cannot use it. I don't see the logic to it either, if you are stunned you cannot really focus on anything at all.

I'd side with you on this one but if your GM disagrees then unfortunately the GM has to be obeyed (wrong though he may be).

Yep. As Calgor says, the Rules As Written and the Rules As Intended are with you.

However, the GM has Rule Zero with him. Rule Zero > RAW and RAI.

I could maybe see a situational case for purely mental actions* if the source was described as being paralytic but was using the Stun rule mechanics.

*Stuff you could fob off onto the other half of a Rite of Duplessence.

Agreed, if the action is done as say an involuntary action or if for example your body is in some hybrid of organic/ AI (or daemon or mix thereof) control and that while you may physically be out of it and stunned, knocked out of sense for a moment, unless that alternative consciousness is also brained as well, then that could theoretically be an argument for the GM ruling for it to be valid. So you might be unable to focus but your daemon guest isnt.

One thing to remember though, these rules work both ways and if your GM has determined that stunning still allows a reaction and it just means you can't evade then that same rule also applies to you as players and you **** well remind him of that every time they may try to stun you.

Player: "Oh you hit me with a shocking mace? Ok, I'll still focus and be ready to hit you."

GM: "Erm no, you're stunned"

Player: "Your own house ruling, you said stun only negates evasion."

Specifically, the ruling in question was made when my Khornate Renegade attacked his Psyker DMPC and stunlocked him with repeated Stun attacks. He used this reasoning to justify the DMPC being able to manifest a Psychic Power while Stunned (because Focus Power is just a mental action of concentration and not a physical one) to retaliate and kill my PC.

Specifically, the ruling in question was made when my Khornate Renegade attacked his Psyker DMPC and stunlocked him with repeated Stun attacks. He used this reasoning to justify the DMPC being able to manifest a Psychic Power while Stunned (because Focus Power is just a mental action of concentration and not a physical one) to retaliate and kill my PC.

No, I'm pretty sure that's your GM being a ****.

Presuming, of course, that your character had good reasons for beating on the psyker. Beyond just "he's a psyker and he's right here". Which, admittedly is often enough justification for many Khornates.

Presuming, of course, that your character had good reasons for beating on the psyker. Beyond just "he's a psyker and he's right here". Which, admittedly is often enough justification for many Khornates.

Khornates need no better reason to slaughter filthy psykers! None of this foul sorcery!

Presuming, of course, that your character had good reasons for beating on the psyker. Beyond just "he's a psyker and he's right here". Which, admittedly is often enough justification for many Khornates.

Khornates need no better reason to slaughter filthy psykers! None of this foul sorcery!

While true, the term "DMPC" implies that it was a fellow party member, rather than a normal NPC. Attacking a party member for the sole reason of "he's a psyker and he's right here", while generally in-character for a Khornate, can be disruptive to the social fabric of gaming - and so there should be in-character reasons to not attack a party member psyker (yet). I'd prefer there to be a greater, more compelling reason when intra-party conflict happens.