I only put in 24 characters because the RNG in my first run was so bad - all of my DPS were benched; then this time I almost didn't have enough characters to get through 2 arcana's and act 10. They should make all the characters in the same element available whenever you get to pick one. If character RNG is bad, then the gameplay is bad, especially if you don't have many built characters (which is the case for me). The additional character buff is useless if you don't get the right characters per round.
First time trying arcana in lunar mode