Within each tier there is no particular order, just groupings with relative power levels between sets being close enough that there was no real need to differentiate
This ability stacks too, so if your bench is full of Iron Crown ex, your active future Pokemon is dealing a whopping 80 more damage a turn
For example, Become Immense technically has a CMC of six, but if you've ever played with or against Death's Shadow Aggro, you'll know that it is most often cast for one mana, so for the sake of our calculations, we count it as one CMC rather than six
Additionally, as they have no DEF, they cannot be in Defense Position or face-down, they must in other words always be in Attack Position, so Book of Moon is not a legal card to target a Link Monster with
So, should you play Cats in Foundations Standard