Reach and how it interacts with various sized mounts.

[Loreguard]

Thinking about another question about lances and reach from Large creatures, and the recent discussion about Tiny riders and small mounts, made me contemplate a potential resolution that might be relevant for both situations.

Riding large creatures reduces a riders reach by 5' make a medium rider on a large creature with a lance have less reach than a small rider with a lance on a medium creature.

Other than that specific situation, the purpose of the rule doesn't seem that hard to fathom. You are after all on something that requires a little extra reach to reach out of your immediate space, so reducing the space seems a little reasonable.

The other situation that seems troubling is that small creatures and large creatures can wield swords to hit adjacent creatures when mounted. However, Tiny creatures are expected to cohabitate the square to attack someone with a sword or other similar melee weapon.

However, Tiny creatures on Small creatures aren't allowed to cohabitate with small or medium creatures an longer, meaning they lose the ability to strike them from their mount at all, unless they have a reach weapon.

What if 5' of the reach lost by wield a reach weapon from a large (or larger mount) could be bought back by the mount spending 5' of its movement moving towards the other square, but not entering it. Allowing the attacker to treat their next activity as if their weapon had 5ft (normally all) of its reach restored for the purpose of a single target.

This could even be potentially used to solve the Tiny issue as well, if you allowed the small mount to spend 5ft of movement to move to the edge of its square, and allow the rider the opportunity to complete one activity as if a single target was within your reach.

I say an activity, but maybe it should only be one attack, but I said activity because I felt like it was worth asking, why not allow a double slice, for instance.

I think that this helps the issue of a small rider on a medium mount having more reach than a medium rider on a large mount, but it doesn't eliminate there being a cost to using the larger reach, but 5' of mount's movement seems like a reasonable investment into getting that reach back.

Anything obvious on how doing that would destabilize the balance of things worse than they are now?

[HumbleGamer]

I like the flavor ( gaining momentum because of the mount movement, and because so performing a strike ).

As for downsides.

- a mature companion only has 1 action to Stride or Strike (no step), resulting into triggering AoO if already next/adiacent to your target.

- Requiring 1 movement to increase the reach would result in 1 attack ( or activity, as double slice ) per round ( unless commanding the companion ).

I though about the diversity in terms of size and mounts too, and considered to make it standard regardless the size of the creature ( mount ).

I mean, regardless your size ( assuming a mount 1 size larger than you ) your melee reach would be any square adiacent to the mount. Using a reach weapon would increase that reach by 5 feet.

So, something like

-Sprite on a corgi mount: 5 feet reach with no reach weapons, 10 feet reach with reach weapons.

-Goblin on a Medium mount: 5 feet reach with no reach weapons, 10 feet reach with reach weapons.

-Human on a Horse: 5 feet reach with no reach weapons, 10 feet reach with reach weapons.

To standardize the rules rather than adding new mechanics.

Using a mount 2 size larger would require a reach weapon to attack adiacent enemies, while a mount 3 or more size larger would require a lunge with a reach weapon ( for example ).