So is there any way of knowing whether a person has been marked other than by the horror making it obvious? I must confess I don't really understand what 'marking' means. It doesn't sound like it requires anything more than a simple act of will, and has no chance of being resisted, or even known about.

Well that is the intended purpose of the Artisan skills. You check and recheck your art looking for hints of corruption.

How does a horror get people marked? Is it a check the horror makes in secret? Does it have to physically touch the victim?

So Grabthar might be corrupted, even though he has absolutely no knowledge that anything is different and that corruption apparently has no influence on his will?

Surely corruption must... you know, corrupt?

I think the idea is that the corruption has to take root, and you can discover it before harm is done.

Sort of like how being tested for HIV can allow you to start treatments well before there is enough of the virus to do harm.

No, he'd be corrupted once he starts listening to it, or once it starts being a continual presence in his mind.

If it has marked him then all he is (currently) is marked.

So (hypothetically) the horror would want to reveal itself, and put him in a position where he had to accept it's help or obey its orders. That'd open the door and start him down the road to corruption.

Being horror marked (in itself) does not remove the Namegiver's free will.

I just started an "If I were the Horror" post and then I realised how silly that was. I have no place speculating what the horror's strategy would be.

In case I am AFK when the shit hits the fan, Atrii's first order of business upon engaging the horror will be to tell Z'phir not to do anything it says. He will trust to the others to offer any necessary justification for that, should Z'phir need it - as he will then immediately begin casting the spell.

I only want to exploit Z'phir's ignorance insofar as it helps us find the horror. I don't want to push the advantage to the point of Z'phir opening himself to new avenues of infestation.

I should've done this earlier, but can we say I changed out my matrices during the downtime?

yes, we can say you did it this morning. What are you having prepared?

Also did you try to learn a spell today? If so what spell?