The following classes work like they do in 5E:


They choose a Realm of Magic (Channeling, Essence, or Mentalism) and gain Power Points equal to their realm bonus (Wisdom, Intelligence, or Charisma) or 1, whichever is higher, at each level.

All other classes don't exist.
Instead, use the classes from Spell Law. In RMU, these are:
  1. Channeling magic-users
  2. Essence magic-users
  3. Mentalism magic-users
  4. Hybrid magic-users