The Oathbound Wizard — Christopher Stasheff

Ensorcelled runes on a scrap of parchment had whisked Matt Mantrell to a world where reciting verse worked magic. There he won fame, power--and the heart of the beautiful Queen Alisande. But then Matt learned that he couldn't marry his true love; Lord High Wizard or not, Matt was only a commoner...

Matt railed against fate. He swore he'd conquer a kingdom, if that's what it would take to claim his bride. Then he found that, in this world of enchantment, such an oath could not be broken. Matt had truly committed himself to win a crown--any crown--or die in the attempt!

In search of lands to conquer, Matt set his sights on neighboring Ibile, where the loathsome Gordogrosso held his throne through vile magics and armies of evil. Matt marched off against the tyrant, gathering such unlikely allies as a surly dracogriff, a well-spoken cvclops, and a chased damsel. But against Gordogrosso's evil genius, Matt was going to need more than a few stout companions and some well-worded verse...