I'd be surprised if Kamoko was a 5 cost card, especially at this point in the storyline. Part of her appeal back in the day was that she was low-cost (for a Unicorn, anyway). You could bring her out first turn and then use her to take an undefended province on turn 2. I'd expect her to be a 3 fate or so when she first shows up.
I'm thinking 5s are mostly going to be clan champions, daimyos, elemental masters, and others of that "tier."