I've started working on backgrounds with Casey and it's been going really well so far. We talked about making the mountain seem more fluid, so he's giving it some more organic elements in the way it folds over itself. The colour also works really well I think, it makes the environment look more surreal. The organicness also works because in a way all of it is his own fabrication, so it's a part of him in that way.
The backgrounds are drawn with ink pens on paper, then scanned and edited and coloured digitally. I've mostly been involved in picking the initial designs from Casey and then working with him on a suitable colour scheme for the shot, and different ones for some (for example morning and night). Most environments need to be flat, but some of them require different layers depending on where the characters are positioned.
Overall I think the background design is going really well, I'm happy I decided to work with Casey on this, the styles seem to compliment each other really well.