Magical Discharge
A Magical Discharge is basically dumping all of your mana into one giant attack. It's like a limit, but any magic character can do it so it's non-exclusive. The attack comes out, usually, like a magic laser that's, dependent upon your mana, capable of leveling a skyscraper. That's as strong as it can be and very few people can do more than one (I draw the line at four) in a day. Like a limit, once all your Magical Discharges have been used, it will leave you incredibly fatigued, but unlike a limit will leave you without the ability to use magic.
If you can fire more than one, your character best only be an avid magical user and have high amounts of mana, making it actually dangerous to use just one. However using a single mana discharge divides your power by 1 of the total amount of your magical ability. Also realize that each time you use a M Discharge, it becomes slightly weaker than the last and more tiring.
Number's and affects shall be determined like this:
A person with 4 MD's (Magical Discharges) has almost not physical prowess at all and relies absolutely on magic.
Each time you use an MD, you loss a level of Magic control. Firaga becomes Firra after first use, Firra becomes Fire after second use and after the third use it is physically demanding to use magic and you feel he affects of your own magic (i.e. fire will burn your hand or heat up the medium, blizzard will freeze it). After the forth you obviously cannot use anymore magic and should be exhausted to the point of collapse.
A person with 3 MD's has some knowledge but only enough to use to run away. After first use, Advancement magic is unusable, after second use, Intermediate magic is unusable and using magic is unusable. After final use you are depleted of your mana and you should feel exhausted to the point of it being hard to lift your weapon.
A Person with 2 MD's can fight but would likely lose if they only relied on their physical skill. After your first use, your magical strength is simply cut in half. After second use, you are exhausted to the point of not feeling comfortable in a fight.
A person with 1 MD has a perfect balance between magic and can fight. After first use, you should feel exhausted and weary, but not enough to not fight on.
If you can use multiple MD's, realize that for every one RP day that goes by, you gain one back.
Also, please be realistic. If you have been waisting mana and are near empty of it when using a Magical Discharge, chances are, you won't be able to fire as many and they won't be as strong.