If, when you click modify, you aren’t able to add more troops, there are several possible causes: Each card represents 1 troop. You may need to acquire more by purchasing boosters or using the market. If you already have more troops, but they seem to have disappeared, try the Graveyard at the Temple to resurrect them. It may be that you’ve run out of feldable CP. If your army size has reached its maximum, you may need to reduce other units or wait until you level up to add these troops to your unit. Some troops are so large that a single troop constitutes a full unit, such as dragons or behemoths (any troop costing 13 CP or more).