Just Read This.

[BlKnight]

Magic, great for magicians, great for summoners, great for necromancers, great for clerics, even great for the general adventurer. Not so great for warriors or assassins/ninjas or thiefs etc.

I suggest you can have abilities that work like spells and drain magic pionts but mave more "physical" effects. Example:

Bezerk Rage-Drains 70% of all your mana points and sets you whirlwind of blade fury that lasts for several seconds and whoever is hit gets their hp slashed in half (ie you have 86 hp left, the attack does 43).

Ninja Stealth-Drains 1% mana point every second in use. For the duration of the effect you do not leave footprints or make noises when you move.

If you think it would seem silly to have mana and physical atatcks in the same league. There could be another bar made but you must choose mana or energy one or the other not both. To learn these things maybe you could undergo training like making logs into pages, pages into books and say beserker rage would take 1 book 10 monster hides, 100 swings of the axe, 100 swings of the sword, 100 throwing of pots. And ninja stealth would require you to give 3 books, and say 25 hiding in barrels and 25 climbing up tress.