Slots for your army. Unit type slot (100 C) - these slots allow you to have creatures of different species in your army. These slots are for average type units, which can only have abilities of a single nature. Supreme unit type slot (500 C) - these slots are for Supreme creatures, which can have abilities of two different natures. (list of all natures in case you forgot: Physical, Fire, Water, Air, Earth, Light and Dark) Subslot (10 C) - if you want to have more than one creature of the same species in your army, you can buy a subslot. However, you can't have subslots for Supreme type creatures. Look at my army project for an example: http://scratch.mit.edu/projects/DragonSpirit/338207
