Magic-use was thereby to be powerful enough to enable its followers to compete with any other type of player-character, and yet the use of magic would not be so great as to make those using it overshadow all others. This was the conception, but in practice it did not work out as planned. Primarily at fault is the game itself which does not carefully explain the reasoning behind the magic system. Also, the various magic items for employment by magic-users tend to make them too powerful in relation to other classes (although the GREYHAWK supplement took steps to correct this somewhat).
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The logic behind it all was drawn from game balance as much as from anything else. Fighters have their strength, weapons, and armor to aid them in their competition. Magic-users must rely upon their spells, as they have virtually no weaponry or armor to protect them. Clerics combine some of the advantages of the other two classes. The new class, thieves, have the basic advantage of stealthful actions with some additions in order for them to successfully operate on a plane with other character types. If magic is unrestrained in the campaign, D & D quickly degenerates into a weird wizard show where players get bored quickly, or the referee is forced to change the game into a new framework which will accommodate what he has created by way of player-characters. It is the opinion of this writer that the most desirable game is one in which the various character types are able to compete with each other as relative equals