Well I have to go with the answer iI usually uses in these debates/questions.
Both a fighter and wizard in cooperation can beat any two fighters/wizards (same level
)
The fighter and wizard covers so different areas that working together will aid both in the cause to win.
The fighter can protect the wizard and give him the time to cast more advanced spells that will aid the fighter in killing the enemies. The fighter can also thwart enemy spellcasters with a distance weapon making it tough for him to get a spell loose.. Also, combat with so few people comes down to time...
one on one... Tough choice, depends on the way you play. A Wizard have to use different tactics and are more dependant to have the enemies gathered to weaken them with area effect spells and also hav to "waste" spells to protect himself. If he runs out os spells, he won´t be much good...
A fighters sword is never dull, he can whack one at a time but is also dependant on finding magic items to protect him from simple spells that can distort his mind or freeze him making him voulnerable.
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WOLF WINS EVERY FIGHT BUT ONE, AND IN THAT ONE, HE DIES