Hi Carlos, our first version of Valley of the Dead King contains deck boxes that are very snug, and do not accommodate sleeved cards. Our future production runs will contain slightly larger deck boxes to fix this. You may find some ideas on BGG here:
Thanks for the question!
We were able to increase the tray container size for our boxes to hold sleeved cards, but were unable to create tuckboxes that large. So while our tuckboxes remain the same size, there is a larger area for sleeved cards in our reprinted volume. We talk about the change here: https://www.kickstarter.com/projects/hexploreit/hexplore-it-the-forests-of-adrimon/posts/2321784