In the best ensemble shows, the original main character evolves to be as weird as the rest of the cast (like Michael in Arrested Development). In less . . . felicitous circumstances, the vestigial main character still hangs around for awhile, getting the occasional plot, but just generally being a drag (let's call it the Peter Petrelli effect).
Anyway, The Complete Warrior (Andy Collins, David Noonan, Ed Stark) is about martial characters in Dungeons and Dragons.
The thing is, I really do think warriors make for great main characters . . . in fantasy fiction. There's a knight who has an epic quest or a callow young farmer setting out on a bildungsroman and they've got a down to earth perspective. They are constrained by concrete issues of logistics and human-scale limitations. "Oh no, the bridge is out, so I guess I'm going to have to ford the river at great personal peril" vs "Oh, hey, look at that bridge down there. It's collapsed. Good thing we're flying on our broomsticks or that would be a real inconvenience. Wait! Up ahead, is that a pink, sparkly cloud of anti-flying dust?! We're doomed!"
If I'm reading a novel, maybe the exact right amount of wizard is just as a wacky one-off encounter - "Here, take this Macguffin. It will come to your aid in your moment of greatest need." The magic user is someone who supports the hero's journey, but can't actually be a major part of it, because then the group's capabilities are basically random.
And the thing about D&D is that it knows this, deep down in its bones. The entire game is subtly structured around it. It is an assumption that drives much of its worldbuilding and plotting. A dragon is attacking the town? That's a job for a knight in shining armor. A cursed item needs to be destroyed in a distant volcano? Better assemble a team of completely ordinary people and one wizard to hike cross-country. There is an unspoken code that governs the maximum amount of magic you can have and still have it feel like D&D-style fantasy.
But then, the structure of the game encourages team-style play, and the Fighter and Wizard are assumed to be coequal roles. But there's no way that was ever going to work. You can't make a team out of a person who risks life and limb to swim across a river and a person who can take a nap and then fly over the river when they wake up. Even if they are relatively equal in effectiveness ("ah, but what if the party is on a time constraint and the wizard doesn't have time to take a nap"), they are living in two different worlds. They are, essentially, playing two different games.
You can see that tendency in full display in the Complete Warrior. Almost everything in this book is great for the sort of game where warriors take front and center, but the driving philosophy behind the mechanics is a bad fit for Dungeons and Dragons as it exists in practice. Basically, warriors are allowed to be impressive, but in order to reach that potential, they must overcome obstacles. They don't generally have abilities that just work, they instead get bonuses that apply under certain circumstances, and their "abilities" are a tendency to succeed more frequently when those circumstances apply.
Take the Gnome Giantslayer as an example. They've got some very impressive bonuses against giants.
You reach level five (making you a 10th level character, at least) and you get the Close Shot ability. You don't suffer an opportunity attack when using a ranged attack adjacent to a giant. And that's pretty useful. Maybe not as useful as being able to cast Hold Monster (which a Hill Giant would need a 15 or higher to resist at minimum), but a very evocative ability. You're a trickly little gnome and you can weave around your foe, pelting them with crossbow bolts. A nice heroic fantasy.
But what happens when you're fighting literally anything else besides a giant? Apparently, you just go right back to being a normal character, relying purely on the numbers from your fighter chassis, because just having the general ability to ignore opportunity attacks triggered by your ranged attacks is "Combat Archery" an Epic Level feat that becomes available at level 21. Canonically, that makes it more powerful than the Wish spell.
You can't just have a class that gets a bunch of generally useful abilities that giants have a particularly hard time dealing with. You have to be a specialist. Because the techniques you develop to fight giants are grounded in a very strict model of learning, where they don't just automatically translate. But a wizard can just copy new superpowers into their book and not even pay an opportunity cost.
I guess it's been kind of a running theme with this edition. I find myself unable to enjoy cool fantasy stuff like warriors turning into bears or holy knights who wage war against demons, because I'm persistently aware of this inequality and it drives me to distraction.
Though in my defense, it's not just me being weird. There's a section about running all-warrior campaigns, and here are some snippets of its advice:
"In a typical party, a fighter can avoid dealing with the enemy's minions because the wizard takes them out with spells such as sleep and fireball."
"Thought a sorcerer may complain about only having two bugbears to incinerate with his fireball, the fewer opponents faced by a fighter simultaneously, the better."
"An often-overlooked option for rangers and paladins is to stock up on wands of cure spells."
"Multiclass fighter/clerics, barbarian/druids, and the like gain access to spellcasting, scrolls, and wands, just as rangers and paladins do."
Like, c'mon Complete Warrior, I'm on your side here, but you have to try just a little harder.
Anyway, my final opinion - this is a perfectly fine book on its own, but D&D 3.5, as a whole, was very often not fine.
Ukss Contribution: This one nearly slipped by me. When I first read about the Gauntlet Guardian, I was mildly amused by the idea of a robot designed to "punch anyone who gets in their master's way." I noted the delightful turn of phrase, but didn't think it was a memorably strong setting element on its own. Then, in defiance of my usual habit, I skimmed the creature's stat block and noticed that, by default they are Small-sized.
Here I was, picturing a human-sized robo-boxer who tagged along with the wizard or sorcerer who created it (because D&D, obviously), but I was meant to be imagining a child-sized robot with oversized fists who will absolutely unleash disproportionate aggression when let off the leash. That's an image that's going to stick with me for awhile.