Like race advantage, each unit has its own advantages and disadvantages against other units. Exactly how they do is closely related to race advantage. Each race has at least one unit that has a disadvantage over another race's unit they have race advantage on. I.e. if Humans have race advantage on Li'thi, then at least one of the Human's units will not have advantage over the other. With 6 units per race, 720 different possible stacking arrangements for each race, and 7 different races, there exist a total of 25,401,600 different battle line-ups and 177,011,200 different battle outcomes.