Cosmic Encounter Card Tray

thingiverse

I used 8X of the player trays from https://www.thingiverse.com/thing:2390899, which barely fit inside the box with those holders. If you have more than 8 colors, they won't fit in the box. This square fits snugly into the corner and holds most cards, including encounter, flair, defender, and destiny cards. Some cards like tech and optional ones don't fit, so I bagged them separately. This setup should work for expansions and sleeved cards, as I have two expansions and penny sleeves. You can download the scad file to adjust or modify compartments as needed. Alternatively, you can try reducing the wall size slightly to gain more space and clearance, but be aware that the tray might become too fragile then.