I have an Impact Character with a secret, and if it’s found out, his life is over, just like a Columbo villain
In my story form his Critical Flaw is investigation.
I have it in mind to read this as he is vulnerable to being investigated and he can’t avoid being found out eventually, all he can do is stave it off until such time as he is able to twist the truth in his favor.
Of course, he’ll lose all credibility with the MC when his real nature is found out. The impact of finding out his lie will be awful but then his influence/impact over the MC will diminish to almost nothing.
If he is the Contagonist, then he has a separate agenda, so might be emotionally independent of being found out with life being over. The impact of the lie is awful for MC, but I was mulling over different ways for the IC to deal with it.
That may be true for the player, but the IC and the Contagonist operate in different throughlines – the Contagonist has a position relative to the OS Goal, and the IC has a subjective role in the story.
In this case, the IC is also a classic Antagonist. I will tweak the character elements as development continues but right now I am working with the 8 archetypes, which completely works for this story. Besides, I need the training wheels on this one, I think.
As long as being investigated is what diminishes the IC’s influence/impact, then I think you have a good illustration for an IC Critical Flaw of Investigation. Granted, I’m not a Dramatica Story Expert.
My first thought was to use it one or more of these ways to diminish the IC’s impact on the MC:
IC physically goes away as a result of being investigated or as a result of investigating something.
When IC suspects someone is trying to investigate him (as an accurate assessment or just paranoia), he physically goes away or behaves in a way that lessens or removes his impact on the MC.
Completely benign “investigations” by the MC cause the IC to blow up or generally act a fool.
Due to paranoia, IC can’t resist continually “checking things out” (i.e. operational security) to prevent being discovered. MC is bewildered, frustrated, left hanging because the IC didn’t show, etc.