Heroic Mime: Even more silent than normal. The only time you'll get a yes or no is when it's time to save.
Idiot Hair: The key charm of his character design is that quail-like hair. When walking through high grass or wheat it's the only way to tell where he is.
Muscles Are Meaningless: Other than a handful of children, every character in the game is taller than him. He barely comes up to shin height to some of the bosses. However, when you're packing a library of spells in your beatin' stick, you don't need to be a bodybuilder to dismantle people.
Standardized Leader: Has no major character traits other than implicitly being brave enough to go out into the world alone to kick ass from hell to breakfast.
The Only One: Brian is the only person in the world to know such a huge variety of magic spells, making him, in theory, the most versatile magician to ever live. In practice, he only needs one more spell than anyone else: the strongest Healing he can manage, Vampire Staff, Avalanche, and the Game Breaker Magic Barrier.
Simple Staff: Albeit a staff that stores all his magic, which makes it hit like a mack truck.
A beautiful young woman with white hair and a slightly detached, dispassionate outlook on life. She follows Brian in his quest, weighing in with tidbits about history, the local scene, and matters philosophical. Given her continual presence, it is possible she was going to fight at Brian's side.
Mighty Glacier: Big, strong, and hypothetically slow (given how you just trade rounds, there's no way to tell if he's actually slow or also a Lightning Bruiser). The big concern is running out of MP trying to whittle down his health, requiring you to bash his skull in at the range he's most comfortable.
Offscreen Villainy: Stole the Earth Orb and beat the shit out of the Kennishire palace guards.
Wake-Up Call Boss: Teaches you how the rest of the bosses in the game are going to be. Unfortunately, given the mild difficulty curve, he's also a...
Warm-Up Boss: ...since those intimidating-looking magma columns are easy to dodge at range.
A twiggy wind magician getting revenge on all those who belittled him.
The Brute: Even more brutish than Solvaring, as he's just a punk kid with a magic artifact.
Lean and Mean: The skinniest boss and the one with the most petty motivation.
A renegade pyromancer currently hiding out in an active volcano.
Macguffin Delivery Service: Was waiting on Brian to bring him the other three gems, so he could kill Brian and take them for himself. Unfortunately, Brian arrives with three gems' power worth of magic behind him...
In the Gameboy Color version of the game, he winds up turning on you.
A recurring foe and one of the iconic enemies of the game, both for its relative difficulty and for its impressive Jay Leno chin.
Boss in Mook Clothing: Wyverns are damned unpleasant to fight. On the other hand they are also perhaps the most common enemy in the game, appearing in two regions. Only Blood Gels and Termants show up more.
Degraded Boss in Mook Clothing: Since they appear in more areas than most other enemies, wyverns eventually become little more than speed bumps as a demonstration of your increase in power. Their Palette Swap Red Wyvern cousins are naturally easier to kick the ass of, oddly enough.
An assortment of oddities out to kill the hell out of Brian. A surprisingly diverse lot, even with the occasional pallet swap and model swap.
Everything Trying to Kill You: Rabbits, hippos, sunflowers, bluebells, dogs, and animate piles of rotting meat. These are the first enemies in the game.