Castle Mac Rules Discussion: Mounted Combat

Mounted Combat is a paradigm I've struggled with from time to time here at Castle Mac. The PHB leaves a bit to be desired, and it can be confusing to understand the ins and outs of mounted combat. This became especially painful for me when we played Cubicle 7's Adventures in Middle Earth Lord of the Rings 5e supplement and I chose to play as a Rohirrim. Disclaimer: We at Castle Mac try to stay close to Rules as Written, including the rule that the DM has final say over any rules, even when they override the Rules As Written. This post is an attempt to collect the printed Mounted Combat Rules, collect and parse Jeremy Crawford's Twitter responses (which are more about Rules as Intended), and introduce a few extrapolations of our own to make Mounted Combat more clearly defined. Some of what I observe below is probably quite obvious to most of you, but hopefully will help others!

Mounted Combat Rules as Written (From the PHB)

Mounting and Dismounting: 

Once during your move, you can mount a creature that is within 5 feet of you or dismount. Doing so costs an amount of movement equal to half your speed. For example, if your speed is 30 feet, you must spend 15 feet of movement to mount a horse. Therefore, you can’t mount it if you don’t have 15 feet of movement left or if your speed is 0.

If an effect moves your mount against its will while you’re on it, you must succeed on a DC 10 Dexterity saving throw or fall off the mount, landing prone in a space within 5 feet of it. If you’re knocked prone while mounted, you must make the same saving throw.

If your mount is knocked prone, you can use your reaction to dismount it as it falls and land on your feet. Otherwise, you are dismounted and fall prone in a space within 5 feet it.

Okay, we're off to a good start. Nothing strange here- it all makes total sense.

Controlling a Mount:
While you’re mounted, you have two options. You can either control the mount or allow it to act independently. Intelligent creatures, such as dragons, act independently.

You can control a mount only if it has been trained to accept a rider. Domesticated horses, donkeys, and similar creatures are assumed to have such training. The initiative of a controlled mount changes to match yours when you mount it. It moves as you direct it, and it has only three action options: Dash, Disengage, and Dodge. A controlled mount can move and act even on the turn that you mount it.

An independent mount retains its place in the initiative order. Bearing a rider puts no restrictions on the actions the mount can take, and it moves and acts as it wishes. It might flee from combat, rush to attack and devour a badly injured foe, or otherwise act against your wishes.

In either case, if the mount provokes an opportunity attack while you’re on it, the attacker can target you or the mount.

Art by JessDoor

Again, this is mostly pretty clear, but it leaves some wiggle room. Questions and observations for me in no particular order:
Observation: The mount must begin and end its activation before you act. This may be obvious to some, but RAW you couldn't have the mount move some of its speed, you attack, then it move the rest of its speed.

Question: It says its initiative matches yours, does that mean it is subject to tie breakers? This really means you must be consistent on whether it acts before or after your activation. Again, probably obvious to many! Because it can act when you mount it, it might make sense to always go after you. You could hold an attack action until your mount moves you adjacent to an enemy to simulate the classic mounted charge.

Observation: Controlled mounts only have three actions: Dash, Disengage, and Dodge. At first blush, that feels a bit restrictive, but for me I think the hangup is "Controlled" vs "Independent". Independent doesn't necessarily mean its not cooperating. For me, that hangup took some thought before realizing something like an intelligent mount (such as one found by the Find Steed spell) would likely follow your direction AND be able to attack your enemies. Note, it would act on its own initiative which could get really hairy...

Suggestion: I might consider cutting the distinction between "Controlled" and "Independent", and instead specify "Trained for Combat" and "Not Trained for Combat" or something along those lines. The distinction would be something like a riding pony who is not trained for combat, and an intelligent, trained steed (such as the one summoned by the spell Find Steed). I would always let a friendly mount act on its rider's initiative, if only for mechanical ease. I would allow a steed that is trained for combat to add the Attack action to the list of options.

Some Twitter Clarifications (Screenshots Thanks to https://www.sageadvice.eu/):

Pretty straightforward, and in line with what we've discussed above.


Again, makes sense. You could replicate a lance charge if your mount does a disengage action and you hold your attack action until you're adjacent to an enemy. It costs you your reaction, but you also have an opportunity to do a ride by stabbing!

When to use Animal Handling?
This should be left up to the DM, but checks should be made when mounts are hurt or spooked (especially if the mount is untrained). In my opinion, the rules are deliberately vague here, giving agency to the DM. The DC should be based on the severity of the distraction and the training of the mount.

In Closing
I hope this has provided SOME clarity that I thought was lacking a bit on Mounted Combat. Again, 5th edition is great in that it leaves a lot in the DM's hands, however, if Mounted Combat is frequent (see: Cavalier) in your campaign, it's likely best to think through the rules framework.