Fantasy novel about a young apprentice switching professions

Question

A novel I read in the 90's or early 2000's.

The hero is a young apprentice to some version of telekinetic wizards. They can attract (or repel) parts of the same object. It is currently a siege and the master uses this power to destroy a catapult.

The siege is successful and the castle is taken. The apprentice escapes with a McGuffin. Now masterless, he starts investigating it.

He starts at the guild of alchemists and learns a few months. They finally figure out it's sorcery.

He spends less time at the sorcerers guild, possibly going underwater? He finally figures out it's some kind of demon summoning object.

Along the way, he learns to fight with sword and shield. His trainer pronounces him competent but too small to be a professional.

Finally,

he trains very briefly as a demon summoner. He summons the arch demon, defeats it and gets on with life. A side plot along the story is the increase in demons due to failed summonings.

Obviously, this should be easy to figure out. Unfortunately, it is remarkably hard to google, as I found out.

Answer 1

Master of the Five Magics by Lyndon Hardy. This is the first book in his Magic by the Numbers series. It was originally published in 1980 so it had been around for a while by the time you read it.

Alodar was a mere journeyman thaumaturge, learning the least of the five arts of magic. As such, he had no right to aspire to the hand of the fair lady, Queen Vendora, not even when he saved her during the siege of her frontier castle. But aspire he did.

The scene with trainer that you remember is:

Cedric stopped and gently rocked Alodar back and forth. “You will never become a great warrior,” he said. “With more training you will grow into someone not to be dismissed lightly. But you are too small and slow to hack your way through a screaming hoard or stand toe to toe with a thick-muscled giant. No matter how hard you try, I do not see you someday beating your chest in triumph on the top of a pile of bloodied foes.”

The McGuffin that Alodar discovers in the besieged castle is a grimoire. More precisely he discovers a previously unknown spell has been written on the inside of the grimoire's dust jacket and he takes the spell with him when he leaves his master to become an alchemist.