Three abilities: it's a starting point. You can go rules-light, and let the players role-play their way to an interesting game, or you can add abilities, add skills, add perks, and get nitty-gritty with the details.
Protection: if a character has protection (of the right ability), he gets to use it to reduce every (usually) die of damage. Your enemy attacks you with a magical, epic trident. It probably does 1d20+1 Physical damage. Whether you dodge that attack or not, you get to roll your protection to reduce that damage. If your protection roll exceeds the damage roll, the hit still does a minimum of 1 damage. Protection can also be used to reduce Mental damage, but with the special spellcasting usage of Metaphysical points, damage and protection should be highly limited with that ability.