If two people were saying that the other killed a third person, who would you believe? Likely the first one to mention it.
You believed him at first, didn't you? Because you had nothing else to compare it to.
Would you accuse your boss, the man "crossing blades with... would mean a death sentence"?
Mercer had the advantage in that he could spin a plausible tale about Karliah's feminine wiles leading to Gallus' ruin. And the guild split to rally behind different leaders -- Mercer killed or had killed anyone who challenged his authority and with it the implicit validity of his story. And if I'm remembering correctly, Mercer was Gallus' second-in-command -- why would he lie, if Gallus trusted him so?
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It's one thing to find a plot hole, and another thing to say there's a plot hole because you can't be bothered to remember the details, or attempt to understand them.
Just hop on that bandwagon. Don't bother thinking about it for yourself. I'm sure the perpetually discontent will tell you what to think.
What details are these? I was asking if the game tells you how he framed her. You appear to be making things up to try to make it all somehow fit together.
I mean, why are we to think people would just believe Mercer's yarn about her 'feminine wiles'? Is there any talk of these factions splitting off and Mercer having all these people killed?
And since when do people automatically believe the first person who says who killed someone? That makes no sense whatsoever.
And Mercer wasn't the boss then. We're led to believe he and Karliah were on an equal footing.
And I didn't believe anything Mercer said. Judging by the way they act, I'd judge both he and Karliah to be totally insane. It's just the game won't let me get them sectioned.