I write fantasy. I'd say for a living, but that implies enough earnings to survive on and that would be a slight exaggeration, like saying a AA battery can run Las Vegas. But its something I have been doing for several years now, and I have a couple of books under my belt.
The strange thing is, I don't read a lot of fantasy. I don't like much, most of it is pretty forgettable or the world doesn't appeal to me. Too much of it is just awful, the kind of earnest nonsense that makes the genre a point of mockery for many people.
Something that often comes up in fantasy books and especially games is the horse. Its a good old fashioned way of getting around; humans have been riding about on horses for thousands of years and they work well.
The problem is in the modern culture, almost nobody has more than a vague familiarity with actual horses and their nature. And worse, being so influenced by modern culture, writers presume things based on their experiences that are nonsense. I'm no expert on horses, but I do know some about them through limited experience and study with folks who are experts.
To begin with, horses aren't cars. I know that sounds kind of obvious, but for some reason when it comes down to fantasy stories, authors seem to forget this. Picture the scene with me now:
Cronan brought his steed to rein, its steel-shod hooves sparking on the rocks as it abruptly pulled to a halt. The sun shone through the leaves of the canopy overhead on his broad, muscled shoulders as Cronan slid off the horse and looked around him. This had to be the place the crone had mentioned, a cave with an entrance like a screaming mouth, filled blackness suggesting death and fear. The vines overhead were growing low, hanging across the entrance as he strode inside, brushing his long black hair. No darkness would stop his mighty sword from finding a sheath of vengeance in the lich this day. He knew it could take him days of searching in the Labyrinth of Fell Desolation, but no matter how long it took, he would take his revenge.
Now putting aside the other problems with this melodramatic scene, think about something here. What happened to the horse? Its not like you can park one and hit the key fob. A couple tweets and the alarm is activated, it will be there when you come back out, right Cronan? Except it probably won't.
Horses are animals, and they have to eat pretty regularly. They wander to look for food, and after a while start looking for company. They aren't incredibly bright, so they will not understand you will be back, or what you're doing. This mighty steed just saw the rider go into a cave and a day later not come back.
And that doesn't even count predators. A big tough horse might look mean and dangerous to you, but it looks like a week of steak dinners to a lion. Any world with liches in it will have nastier stuff than lions to deal with, as well. That horse probably won't survive 2 days in the middle of the wilderness. If it does, it will be miles away, having run from everything it couldn't stomp on (assuming its a warhorse) and Cronan will have to either track it down or hoof it with that big treasure chest on his back.
Which brings us to another problem. Cronan the Barbarian is a typical mighty hero type, with shoulders so wide he has to go through doorways sideways and his 7 feet of muscle can bench press an ox. That's great, but what horse is going to carry this guy?
He can get by with some gigantic draft horse type like a Clydesdale or Frisian, but not many others. Your plain vanilla riding horse can carry a huge person like that, but not very long without trouble. Don't get me wrong, a horse will go as long as you drive it to, they're dumb and very hard working when pushed to it. But they'll die if you force them to carry a huge weight too long.
The only book I've ever read that even brought this up was Treason's Harbor by Patrick O'Brian. His main hero Captain Aubrey is a big guy who varies in weight based on his riches and how long he's been at sea, but is a big fellow, and he needs a big horse to carry his weight.
But let's assume our hero found a huge horse to carry his huge frame; and armor, because only an idiot goes adventuring in a loincloth - a soon dead idiot - and that weighs a lot, too, Plus all those weapons, food, bedroll and... well that's another post, I suppose,
Even a big, strong horse is still basically a horse. And they survive by running away. Not just running fast, but running first. The first instinct of a horse when confronted with trouble is to run away. And to make sure, a horse will assume pretty much everything is trouble.
Yes, you can train a horse to be mean, aggressive, and combative. You can train a warhorse to kick and bite and ignore the sounds of combat, but you can't train a horse to stop being a horse. That training will only take you so far, and will not remove its basic herbivore prey nature.
And that means the brute will sometimes think, without warning, that a rock is maybe a tiger and freak out on you. It means that sometimes when a bird suddenly flies in front of the horse, it becomes terrified.
You see, horses don't have a fight or flight response. They have a flight response. You can train them to use their "fight over a mate" instinct on your enemies and you can get a stallion to emphasize their dominant nature over other horses, so they are mean and bite people. But they're still made to run away when they face trouble.
When we see something strange or spot something that looks scary at first glance, we have a lot of options available to us, like examine it closer, go kill it, run away, hide and see what happens next, and so on. Horses have one option when they're surprised: run.
We both have the same "what the--?" reaction when a quail explodes out of the grass in front of us, we both get that startled feeling, heart racing, skin prickling, step back in astonishment and so on. The horse responds in fear and the need to get away fast so it won't be eaten. Even the big mean warhorse.
Now, a well-trained, well-handled horse can be controlled sooner and won't have as many of these episodes, but they still have them. Those mean little scrubby tiaga ponies that the mongols rode were less panicky, but still were panicky.
Because the horse is an animal, not a car. It doesn't just drive where you point it, its a creature too with its own personality, inclinations, fears, and desires. It has a mind of its own, and won't just go from point A to point B without any complications or events, and it won't just sit and wait until you get on next time for a ride.
Horses are pretty needy animals. Part of their physiology requires that they keep moving, its why they stamp and move about restlessly, it keeps blood flowing through their long legs. They have little skinny legs and a big heavy body; that breaks easily. More primitive and less bred horses suffer less from this, but its still an issue. They need a pretty constant amount of food and huge amounts of water to keep going, you can't just ride them around and fill the tank every few days. They need rest.
This is an issue that most writers don't seem to get either; horses can't carry you and all your stuff indefinitely. They have to stop and take a breather. Yes, they're way stronger than you are, but its like carrying your toddler around. That little guy couldn't win an arm wrestling contest with you even using one finger, but you can't carry him all day without noticing the weight and needing a break.
That means no "riding for days" or you get what you see in Gladiator when he reaches his farm: the horse collapses and dies. Horses are kind of stupid when it comes to running for you, they'll do it as long as you compel them to, but their bodies won't hold up under the strain.
And I'm not even going to get into the whole mare-in-heat thing (good luck restraining your warhorse then, tough guy).
So if you're writing horses in a story, try to keep this all in mind. Its not that you have to have gritty constant absolute reality. Nobody needs to hear about how often the horse urinates or combing burrs out of their mane, but just don't treat them like an inanimate object, either.