Cards inside are from 2 core sets (leaving aside the cards that are x3+). There's a lot of space for upcoming expansions. Yihaaaaa!! (Also, I hoard 700+ card sleeves, to treat all my newcomers).
The inserts are made of foam, at 2 different heights, made so to accomodate and hold the rulebook. The foam panels are glued to the box by means of card strips. It's really sturdy, and somehow the box has the perfect measures to get all the cards tight and tidy inside. It took me about 2 hours from start to finish. The plastic thingies are meant to be the burning tokens. I have ordered another set to replace these, in red and yellow, and with the word 'fire' written on them. I think it enhances the dramatic effect of having a zone burning in flames.