His friends at odds, what will Kale do!?
I almost wish I'd had a proper scheme to oppose Hireshmont because that would've been fun. There's not really a 'Quintus' side' in this that I can see, though. An army took over his castle and he promised to behave. If Terran falls, it won't be because Quintus didn't fight to the last man.
In other words, even if Quintus does do something to defy Hireshmont's plans (whatever those plans are), I'm not sure I see how it could be a strong enough move to make a difference. At best he could save Aurvandil a week of effort.
I'm all in favor of intrigues and there were some discussed a while back, but they didn't happen for various reasons. The 'senate trial' seems like a weirdly-timed power play against someone who just lost the power he had. So Hireshmont could ban Quintus...Aurvandil takes the Chateau. Hireshmont doesn't ban Quintus...Aurvandil takes the Chateau. If Vellos has a rabbit to pull out of his hat, Quintus being Duke or not or banned or not can hardly make a difference.
