Clarification on Mounted Combat and Polearm Reach

[HorstStonewall]

So my Paladin is going to do his best to stay on his mount in combat, using his steed summoned using the 'Find Steed' spell. He is also wielding a Glaive, with the polearm master feat, granting him a reach of 10ft with his weapon.

However, being mounted on a warhorse which is counted as a Large creature, means that rider and steed together occupy a 2x2 square (10ft by 10ft). How does this work for calculating reach for attacks, and more importantly the opportunity attacks provoked by PAM.

1)Is the rider considered mounted in the centre of that 2x2 square, meaning I threaten 5 feet to one side of the square, then another 5 feet outwards for a total of 5 foot radius

or 2) Is the rider considered as occupying the whole 2x2 square with the mount, meaning I threaten a full 10 feet radius out from the edge of the 2x2 square?

Thanks for any clarification, first time using mounted combat and trying to wrap my head around this before my game on Saturday

[Man_Over_Game]

You might be confusing rules from prior editions.

From the Lead Designer, Jeremy Crawford:
"Being mounted doesn't change your character's size." (https://twitter.com/JeremyECrawford/status/928363566163308544)

However, when using a grid, you can fit your character on any square on the mount's spaces by spending your movement:
https://twitter.com/JeremyECrawford/status/928372757758320641
https://twitter.com/JeremyECrawford/status/928366740886601728

[HorstStonewall]

So according to JC, I can be in any of the 4 squares taken up by the horse. That seems an odd ruling, since a monster with a 5ft reach could be next to my horse but unable to hit me?

I might have to leave it to DM's discretion then, that's a feelsbad for both enemies and players, if you can't reach enemies adjacent to your horse and they can't reach you. I guess you could flavour some of it as turning the horse away from the enemy and back towards it on your turn?

It feels like there's not any RAW on this, especially since JC isn't gospel, and has been plenty wrong in the past

[Man_Over_Game]

So according to JC, I can be in any of the 4 squares taken up by the horse. That seems an odd ruling, since a monster with a 5ft reach could be next to my horse but unable to hit me?

I might have to leave it to DM's discretion then, that's a feelsbad for both enemies and players, if you can't reach enemies adjacent to your horse and they can't reach you. I guess you could flavour some of it as turning the horse away from the enemy and back towards it on your turn?

It feels like there's not any RAW on this, especially since JC isn't gospel, and has been plenty wrong in the past

Yeah, it's definitely one of the weirder things I've read, and there are a lot better solutions than that. But, as it is, there isn't any real info on where exactly the rider is.

[Snails]

It is realistic that being able to hit the horse does not automatically mean you can hit the rider.

It is fair, because the negative consequences apply to both the rider and the non-rider.

It is fair, because the limitations are removed by simply moving a little (in almost every case).

From a strict reading of rules, if the rules do not say a Medium creature is now Large because he is mounted on a Large creature, then the Medium creature stills takes up a Medium space, and every that follows follows.

It is only weird insofar as we are not used to tracking the exact location of the rider in these situation, from our (presumably) 3e experience. It is quite easy to do so, once we decide to do it.

[Christian]

It is fair, because the negative consequences apply to both the rider and the non-rider.


Well, usually. This is an interesting edge case ... There will be opponents who are out of melee range of the character and can only attack his mount, but who the character can hit with his reach weapon just fine. Of course, after the early levels, the mount probably has worse AC and hit points then he does, so they'll just cut down the mount instead, and ... wait, hold on. I think the Mounted Combatant feat suddenly quit sucking.



Mounted Combatant
... You can force an attack targeted at your mount to target you instead.


Does that mean if you're on a mount but outside your opponent's reach, you can turn an attempted attack on your mount into an auto-miss on you? Well, well, well, isn't that interesting ...

[Snails]

Well, usually. This is an interesting edge case ... There will be opponents who are out of melee range of the character and can only attack his mount, but who the character can hit with his reach weapon just fine. Of course, after the early levels, the mount probably has worse AC and hit points then he does, so they'll just cut down the mount instead, and ... wait, hold on. I think the Mounted Combatant feat suddenly quit sucking.

Well, yes, there are real world reasons that mounted combatants and anti-cavalry infantry favored longer weapons. Basically, it truly sucks to use a sword against someone riding a horse. Mounted with a sword can be done, but it takes a lot of skill, and, yes, it is easy to make a positioning error and not be able to attack your intended target.

Being mounted slightly improves the value of reach weapons, while mounted combat is still undermodeled overall IMHO.



Does that mean if you're on a mount but outside your opponent's reach, you can turn an attempted attack on your mount into an auto-miss on you? Well, well, well, isn't that interesting ...

While not the craziest rulelawyerism I have seen, I would not allow it. I would say the target shifting by the rider either outright succeeds or outright fails.
If it outright succeeds, the rider is the target regardless of what the lay of the map says, presumably because the rider imposed himself to protect the mount.
If it outright fails, then the attack on the mount proceeds as usual.

[Laserlight]

I'd say that mounted, you're 1 wide x 2 long x 2 high.

[HorstStonewall]

I'd say that mounted, you're 1 wide x 2 long x 2 high.

The PHB does say that a large creature is 10ft by 10ft, which would imply a horizontal square. However, it does then say 'A typical Medium creature isn't 5 feet wide, for example, but it does control a space that wide'

So you could argue that you're 1 wide, 2 long and 2 high physically, but you control a space 2 wide, 2 long and 2 high, a 10ft cube essentially, which would make sense

The only issue then, is where the rider is 'technically' located for the purpose of calculating his reach with weapons, especially polearms, and there's almost no clarification one way or another, other than 'work with your DM'