I have had this concept in my head for literal years, and I finally designed it. So bare with me whilst I go into detail:

If you aren't a fan of EXO, just to give a quick rundown, their album names match their group name: Exodus, Exist, Exact. And their logos are all the same overall shape, just changed for each album to match the concept! They have a whole backstory that I won't get into but just know it features the tree of life. Now.. onto Exogen. 

Exogen is an old term that is about tree growth rings. So I thought that would be a perfect album name for EXO given that a big part of their lore surrounds a tree. And it gives a great opportunity to have their logo be a cross-section of a tree showing the growth rings. Regarding the art direction, it would be a very Greek god in the modern day. Capes, gold embroidery, goblets, old paintings, and stone statues.  

The album cover features a gold reflective overlay over the title, as well as a sticker that's on the outside plastic covering that fans can peel off and put on something else. Within the album would be an envelope that holds the CD, postcard, and two photo cards.