When you ask people about the tropes of the fantasy adventure narrative, there’s a genre of those tropes that 4th edition D&D — which is the best D&D, by the way — handles badly. Well, not badly. Well, badly. Well, some of it is bad. Well, some of it is unreliable. Well, look, it’s complicated.
I refer to the idea of a character on a mount.
3rd edition mounted rules were absolutely gonzo. It was one of many sources of damage multiplication and was even the source of where a lot of people learned how 3rd edition handled multiplying damage. If your campaign didn’t actively work against it, a mount was a really strong power option. There was the standard Paladin, with their Pokemount (you could just summon it!), which was a perfectly strong out-of-the-box character if you could just keep finding excuses to charge enemies, and then the permutations of that depending on the campaign. If you couldn’t bring a horse everywhere, there were options like riding around on a lion (I don’t know why I thought that was less obtrusive than a horse), or if you really wanted to make sure you could always charge things, you might even go so far as to play a halfling or gnome (a heritage with a strength penalty), because being able to occupy ‘normal’ sized spaces on your wardog mount was worth the multiplication and boosts you could get out of charging on a mount.
Anyway, mounts, 3e, they were really strong and had heaps and heaps of support. Mounts were strong early on and very strong late, and you could be strong in the early game with almost no support. If you were Big On Mounts, and 4e came out, you were almost immediately disappointed, as a wealth of support including Supermounts and Charge optimisation was vaporised and replaced with just Mounted Combat:
Benefit: When you ride a creature, you gain access to any special mount abilities it confers to its rider. Not every creature has these abilities. The Dungeon Master’s Guide has more information on mounts and mounted combat.
While you are riding a creature, the creature can make any Athletics, Acrobatics, Endurance, or Stealth checks using your base skill check bonus rather than its own if yours is higher.
The DMG has a chunk of rules, as outlined, which are odd. They describe a need for all mounts to be Large size minimum, made mounting and dismounting an entire standard action, judgment call penalties to things that would bother mounts imposing penalties, and a rule that presented ‘prone’ as dreadful for mounting.
See, when you get proned, and you don’t have a mount, it’s a move action to stand up. In the action economy of minor-move-standard, move is your second ‘biggest’ action. It’s not as good as a standard, but it does a lot of stuff.
If you’re mounted, and your mount gets prone, your mount is prone; you are dismounted. To undo the prone, the mount has to spend a move action to get up, then you have to spend a standard action to get back on the mount, meaning that you conclude the turn after a proning with a minor action left. This means that instead of forcing you to stay in a location, proning a mounted combatant means you either turn off their mounted combat entirely, or proning deprives them of most of a turn.
There are enemy monsters with at-will attacks that prone on every hit at level one.
These rules were bad. You wouldn’t get much out of having a mount, mount powers needed a feat to access, you were vulnerable to a status ailment in a way that nobody else was, and you had paid a feat and gold to get here.
Okay, so the rules sucked in the first release of 4th edition. What makes mounted combat interesting is that what followed was multiple attempts to overhaul the system without looking like an overhaul. The two major revisions came in the Essentials and Rules Compendium write-ups, which just happened to include rules changes, but also spoke as if they were just ‘clarifications,’ that ‘superceded previous explanations.’
This didn’t get people to use mounts, though. Mounts went from being dreadful, to just being value neutral. They didn’t offer you exciting strong options until the introduction of the Mounted keyword in Mordenkainen’s Magical Emporium, a weapon keyword that is represented by one weapon, which isn’t very good, and the Dragon Magazine update to the Cavalier class from the Essentials rulebook. The Cavalier was the impetus for me to learn the mounted rules, because years after the game had stopped producing rules and moved on to 5th edition, I thought a Cavalier would be an interesting tool for overcoming some problems I was having with the Paladin.
The rules I eventually pieced together from these three revisions is a bit paperjammy. There are some overlapping errors that the last source replaces. There are some rules holes the final source doesn’t cover so the conflict in the previous two has to be considered. Overall, mount rules work, but they’re not great, and they’re also kind of counterintuitive. Like, you’re required to keep track of ‘where’ in the mount’s space you are, and small characters still have to mount up on creatures much larger than themselves for no adequately explained reason.
I really like 4th edition, but this is one of the ways it’s weak. An attempt to address a problem from a previous edition (the overpowered 3e mount) resulted in an overcorrection that left an honestly interesting part of the game a bit malnourished. There’s one class that really wants anything to do with mounts, and for everyone else it’s just… a bit of a dead feature.
It is a nice feature for the cavalier, don’t get me wrong, but it is a bit of a bummer that for most characters, a mount really isn’t worth spending money on, let alone anything else.