When riding a large mount, what space do I threaten from / what spaces can I attack?

[Rylar]

The questions applies to both normal and reach weapons.

[Java Man]

You share your mount's space(s), so you use your normal reach applied from a large spacw. Mounted combat section in the CRB spells this out.

[Chess Pwn]

pretend you are the size of the mount with the reach of your normal size.

xxxx
xhhx
xhhx
xxxx

So if you're on a horse with a sword you hit the x's

if you have a reach weapon you can't hit the x squares but can hit all the squares next to the x squares.

[Slim Jim]

It's what makes Mammoth Rider so much fun: you're Enlarged atop of huge mount with a 20' polearm exercising battlefield control over an area 55' across.

[Azothath]

For medium size creatures increased reach only threatens the outer perimeter of 5 ft squares. The minimum and maximum reach are increased.
Rounding at the corners due to the way length is calculated (5,10,5,10,...) was done away with giving the corners for medium creatures at 10ft reach. I'd just carry on this simplification OR if you round off the four outer corners give the attacker the four inner corners keeping the number of threatened squares the same. It's hard to make out exactly what text in Sarissa means.

to illustrate;
normal medium creature with 5ft reach (so 5ft is the 'depth' of the reach), C-creature, T-threatened square
[_][_][_][_][_]
[_][T][T][T][_]
[_][T][C][T][_]
[_][T][T][T][_]
[_][_][_][_][_]

normal medium creature with weapon having 10ft reach
[_][_][_][_][_][_][_]
[_][T][T][T][T][T][_]
[_][T][_][_][_][T][_]
[_][T][_][C][_][T][_]
[_][T][_][_][_][T][_]
[_][T][T][T][T][T][_]
[_][_][_][_][_][_][_]

normal medium creature with weapon having 15ft reach
simplistic
[T][T][T][T][T][T][T]
[T][_][_][_][_][_][T]
[T][_][_][_][_][_][T]
[T][_][_][C][_][_][T]
[T][_][_][_][_][_][T]
[T][_][_][_][_][_][T]
[T][T][T][T][T][T][T]
or with rounding (I think this is what the Sarissa is trying to say, choose a 90 degree cone centered about a cardinal or ordinal direction)
[_][T][T][T][T][T][_]
[T][T][_][_][_][T][T]
[T][_][_][_][_][_][T]
[T][_][_][C][_][_][T]
[T][_][_][_][_][_][T]
[T][T][_][_][_][T][T]
[_][T][T][T][T][T][_]

For large creatures the perimeter would be two 5ft squares rather than one. The inner squares as with 5ft reach would not be threatened.

okay...
let me start off by stating that the mounted rules are somewhat undefined. There are many cases where a GM is going to have to make sense of the rules. I'm going to take a simplistic approach.

riding a mount blurs exactly where you are until you attack.
For a medium creature on a large mount, C-creature, M-mount
[C][M] [M][C] [M][M] [M][M]
[M][M] [M][M] [C][M] [M][C]
being roughly equivalent, until you attack then it is set until your next turn. So if you take an AoO that will set your position for the round.
Ride By Attack may let you reset, again a GM option. The simple answer is that you have defined your position on the horse for the round, for good or bad as Ride By only lets you split your movement, not attacks.

[Chess Pwn]

So you're good on a lot until you get to the mounted part. While mounted you're in ALL of the squares of your mount at once. Not only one square that's locked in, you're in ALL squares.

[dragonhunterq]

Azathoth, you are wrong about the rules on mounted combat, they are quite explicit and stated repeatedly above.

mounted combat wrote:

For simplicity, assume that you share your mount's space during combat.

You are in all of your mounts spaces simultaneously. you can attack and be attacked as if you were in all of your mounts squares.

I'm also pretty sure you are wrong on the reach, but I will come back later after I've researched it proper;y.

[Chess Pwn]

His reach for medium people is correct.

[TrinitysEnd]

Sarissa uses the rules for 15ft cones.

[T][T][T]
[_][_][_]
[_][_][_]
[_][X][_]

[_][_][T][_]
[_][T][_][_]
[T][_][_][_]
[_][_][_][X]

So you only threaten those squares like that. T = Threaten

[Azothath]

ChessPawn & dragonhunterq

thanks, we'll see what you find out.

That would change the illustrated base to
normal medium creature with 5ft reach on a large sized mount (so 5ft is the 'depth' of the reach), C-creature & mount, T-threatened square
[_][_][_][_][_][_]
[_][T][T][T][T][_]
[_][T][C][C][T][_]
[_][T][C][C][T][_]
[_][T][T][T][T][_]
[_][_][_][_][_][_]

[Azothath]

illustration of normal medium creature with 5ft reach on a large sized mount (so 5ft is the 'depth' of the reach) wielding a weapon with 10ft reach, C-creature & mount, T-creature threatens square
simplistic reach
[_][_][_][_][_][_][_][_]
[_][T][T][T][T][T][T][_]
[_][T][_][_][_][_][T][_]
[_][T][_][C][C][_][T][_]
[_][T][_][C][C][_][T][_]
[_][T][_][_][_][_][T][_]
[_][T][T][T][T][T][T][_]
[_][_][_][_][_][_][_][_]

[dragonhunterq]

So Azathath, looks like I owe an apology, you are mostly correct. The 10' reach, you threaten the diagonals, but that rule doesn't extend to 15'+. For 15'+ reach, squares count their normal distance. So your 'rounding' example is the correct version, the 'simplistic' version could be a houserule, but I'm really not sure it's any simpler and could end up confusing matters - people should really get used to counting diagonals properly for movement.

If I'm honest I never properly looked at your 15' rounding example until this morning - it was your 15' simplistic that set my alarm bells off. Sorry.

[Azothath]

With the FAQ on the 10ft reach I think opinion will be split. It's easy to extend the simplification, which is why I named it Simple. As long as the number of squares remain the same I don't think it's a big deal, just GMs need to be consistent and stick with one or the other.

I still think the rules are somewhat fuzzy as combat rules are really designed for a medium creature of 1 square or one whose size matches its reach, so corner cases are going to pop up with mounts. There is also a lot of churn over these issues which indicates it's not clear.
My expertise lies more in spells and magic. The volume of spells and interactions makes it complicated. Martial combat usually isn't that complex.

[Slim Jim]

Slim Jim wrote:

It's what makes Mammoth Rider so much fun: you're Enlarged atop of huge mount with a 20' polearm exercising battlefield control over an area 55' across.

Let's check out one them bad boys:

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[_][_][_][_][_][_][_][_][_][_][_][_][_]
[_][_][_][T][T][T][T][T][T][T][_][_][_]
[_][_][T][T][T][T][T][T][T][T][T][_][_]
[_][T][T][T][_][_][_][_][_][T][T][T][_]
[_][T][T][_][_][_][_][_][_][_][T][T][_]
[_][T][T][_][_][C][C][C][_][_][T][T][_]
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[_][T][T][_][_][C][C][C][_][_][T][T][_]
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