due to there being five Vale students, there are many ways we can go about this. 

a team of 2 and a team of 3

two teams of 2 and one team of 1

or a team of 4 and a team of 1.

Now, what I mean by this is that which ever way we go, the members of the team that do not have four players will create additional NPCs to fill in the slots, and those NPCs will be fair game to whatever Raijin, Kouki, and myself have planned.