Yesterday on her tumblr, Cassie posted a few answers to questions about first editions of City of Heavenly Fire:
Hi Cassie! I just wanted to ask if there were any special perks to pre-ordering CoHF? Like how CP2 had the family tree. — cityoftoomanyfeels
Yes, there is! There will be an illustration printed on the inside cover of the North American first editions of City of Heavenly Fire. There are of course two figures on the proper cover of the book, but other characters, some who we’ve never seen on covers before, will be on the inside of the first edition’s jacket. And that’s all I can say right now …
Can you pre-order CoHF in the UK? And will there be any special perks? — jack-jack-attackk
You can always pre-order books. You can do it online, or by walking into any bookstore with the title and author and saying you want to pre-order. You can do it in any country, in any language, anywhere in the world. I’m sure Walker UK will want to do something special for CoHF but right now I don’t know what. I have information only about the North American hardback first edition. I don’t have info about anything that might be available in any other language or version or country right now. "
Just wondering will the picture on the inside of the jacket of CoHF have spoilers? I admit I wish I hadn’t noticed the inside of the jacket on Clockwork Princess until I’d finished the book. — lindybell21"
Yeah, that was really stupid of us. I don’t think we’ll ever do that again. The tree should have gone in the back, even though it was pretty on the inside cover. I don’t think it ever occurred to any of us that people would take the jacket off the book before they started reading, but of course people do, to preserve the cover, etc. And while the tree didn’t tell the whole story, it was spoilery. So no, we’d never do anything like that again. What the CoHF special first edition cover offers is basically a chance to see Cliff (the cover artist who has done all my covers) do his take on characters that would otherwise not make it onto covers, especially since this is the last book about them.