- The way Umbar is set up as the overarching antagonist is terrifying, not because of sheer power or scale (though it's soon revealed that they have no shortage of both), but because they are so insidiously subtle in expanding their empire. Case in point: the Braavosi Tolomei in Chapter 21. Put yourself in this guy's shoes; his city's heard no word from Qarth in months, there have been no ships coming in from the Jade Sea for over a year, Ghis and a good chunk of the far east of Essos basically went dark all of a sudden, and no one has any idea why this is happening. All anyone knows is that something bad is happening out there, and it's slowly making its way westward. Brrr.
- Even when Anarion uses a Palantir to try and see what's going on, all he gets is hazy pictures that offer no hints. That alone is cause for alarm, because blocking out the sight from a Palantir is no easy feat, which means that someone, or a collection of people, have some serious magical chops.
- Then there's Umbar's conquest of Meereen in Chapter 22, where it's shown quite plainly just how cruel they can be. On her way towards Umbar's main camp, Daenerys comes across a village that has been completely massacred, down to the last child. And not in the normal hack-and-slash way, oh no. The Umbarians went the extra mile and hanged them all from trees. How many trees? Three? Five? A dozen? Try hundreds of them.
- Even scarier is the reactions of the Black Numenoreans that are with Dany: they regard the whole scene as nothing more than a stroll through a park and even go so far as to engage in small talk and laugh whenever they pass a tree. If there was any doubt that Umbar is not nice, this pretty much put that to bed.
Nightmare Fuel / The House of Elendil