So, this is a thread about developing out Mounted and Flying mechanics for combat. I thought I would post because my group has hit a bit of an impasse, and I figure it can't hurt to get additional thoughts and ideas. The standard 5e stuff doesn't work for us -- we have some players that want to have car chases and fight mounted battles with a bit more crunch to them.

 However, when it comes to Mounted and Flying, the creature's Dex sorta takes over right now (and we are arguing about the handler's Dex or AH skill versus the mount's Dex, but we all agree that Dex is the flying score, and we are aware that the default rules don't actually specify). Our issue is the DC for the maneuvers, and what the maneuvers should be. We are well aware that we are expanding the three options of mounted combat (dash, disengage, and dodge), and that isn't "rules as written" -- we aren't trying to keep that part, but we are continuing to use the rest of the existing mounted rules.

For Mounts, we have determined the following Maneuvers:

• Walk -- Normal Speed of Mount (which can be anything from giant birds to wolves, to horses to dinosaurs)
• Trot - Medium Speed
• Canter - Quick Speed. Invokes fatigue at 4 hours.
• Gallop - Full out speed. Invokes fatigue at 2 hours in our system.
• Dash -- as normal
• Disengage -- as normal
• Dodge -- as normal
• Shift -- Change speed up one or down one
• Stop - Stop mount
• Turn - Turn mount
• Spin - Spin Mount
• Jump -- Jump over something
• Collide -- run mount into/over something
• Close - Get close to a target (such as a person, other mount, or vehicle, in prep for something)

For Flying (which will include swimming and burrowing), we only have these:

• Turn
• Spin
• Surface
• Dive
• Hover

While we do have some basic outlines for attacks, those aren't our issues. We resolve them pretty much as normal. Our thing is the movement of the mounts and people and what our reference point will be for the difficulty check of doing these actions (the rolls add chance, variable outcomes, and drama -- again, the chase concept, weaving in and out of spaces for flyers while being pursued, or the equivalent of car chases or mounted fights).

 So what I am looking for are your thoughts (constructive, please),  on what we could use for the DC relating to the maneuvers (moves), if there are any movements we sora forgot in our focus blindness, and anything you would like to see in relation to a set of rules for mounted combat.

In my current campaign they all wanted flying to be a theme. 

So I limited all flying to be not more that 2x their current movement speed high (world rule) thus flying ships can fly higher. 

Brooms have disadvantage to attacks while flying as you need to hold on. I gave them all brooms and Flying is not so OP in dungeons but a tool to solve puzzles and joy of movement.  

Mounted combat i use animal handling and reflex (dex) checks, sometimes STR to hold on and not get knocked off.

I like to let the player describe how they are attacking and moving and I toss out Checks accordingly 1s fail, and the higher the score the more exact or better they do. It s been really fun and the players love it. 

Hope this helps

Quote from CaptainLunaSea >>

In my current campaign they all wanted flying to be a theme. 

So I limited all flying to be not more that 2x their current movement speed high (world rule) thus flying ships can fly higher. 

Brooms have disadvantage to attacks while flying as you need to hold on. I gave them all brooms and Flying is not so OP in dungeons but a tool to solve puzzles and joy of movement.  

Mounted combat i use animal handling and reflex (dex) checks, sometimes STR to hold on and not get knocked off.

I like to let the player describe how they are attacking and moving and I toss out Checks accordingly 1s fail, and the higher the score the more exact or better they do. It s been really fun and the players love it. 

Hope this helps

It Somewhat does.

We have skyships, brooms, carpets, spells (of course), one flight capable species (Faery), one swim capable species, and adventures where all of it will be a thing (if they pick the threads) in an open world.

Proficiency is a thing -- you have to have requisite skill (piloting, riding, flying,) to be considered proficient (and if you have it as a speed you are proficient), so that we can have fun with "I am flying and don't know how to fly". 

Flight ceiling is around 300 feet, really, though I am glad you brought that up. Since I anticipate strafing attacks, ramming, and other odds and ends. We also plotted out all the speeds up through 125 miles an hour (Speed of 1100) and speed has an effect on difficulty (+7 to DC at 528, which is 60 mph) and everything has a speed rating (the train is pretty fast at 65 mph, dragons cap out at a flight speed of 300, or about 35 mph). Then we have an acceleration maneuver for vehicles we should probably apply across (it is there for mounts, called "shift").

Works for vehicles which need time, not so much for beings, who do not.

We do get a little more involved than you do, so we still need a way to incorporate it into the combat rounds as a part of the action economy system.

But the DC is what is holding us up -- you mention anima ahandling and reflex checks -- but no DC, lol.  We know what to use for the check, we don't know how to set up the base Difficulty that is then modified by the actions taken (including combat).

For example, two broom riders are zinginging along at a speed of 100 down an alleyway in a crowded market town.  That's around 12 mph, so not killer fast. THey are engaged in a sword fight as they go, and they have a dead break wall coming up at them in 90 feet. If they break off, it opens them for oppo attacks. They can choose what they want to do in this round for an attack, for a movement, and, depending on their features, possibly a reaction or Bonus action.

They can only change direction on the brooms with their move action. They both choose to attack, then they have to make a move action, and one decides to try and stop and the other chooses to try and pull off a 90 degree turn straight up (climb) and then on next round will strafe the other broom rider.

What is the DC for the check for the stopping person (who at the end of their turn will be really close to the wall) and what is the DC for the person who chooses to go straight up?

I'm saying a base (well, the broom has a 12, since it is a vehicle, technically, but I am pretending it isn't) should be a 10 plus the modifiers for the combat and turning.

For those actions it is +1 for combat, -1 for speed, +1 for stop. The Turn has a +3 for 90 degree and a +1 for climb, so modifiers for the Stop are +1 and the turn is +5.

So my approach says the person stopping only has a DC of 11, while the person making the turn has a DC of 15.

But others have different ideas, and I thought I would see what folks think here.

For mounts you also need to consider the mental state of the mount:

Mental State

Each time a mount or creature pulling a vehicle takes damage, they must make a DC 10 Wisdom saving throw. On a failure, they become panicked.  A  creature with fewer than half their maximum hit points or within 5ft of a panicked creature has disadvantage on the save. A panicked animal must attempt to increase its speed on each of its turns, and has disadvantage on ability checks to change direction or make maneuvers. A creature within 5ft of a panicked animal can use an action to make an Animal Handling check (DC 10) to calm it down, on a success they remove the panicked condition. 

Changing Speed

Speeds: Stop, Walk, Trot, Canter, Gallop

When the mount attempts to change it's speed it rolls a Strength check. It can change its speed up to a number of levels equal to the result of the check divided by 5 (rounded up). E.g. a 14 Strength check = can change from a Gallop to a Walk.

Moving through an area of difficult terrain automatically decreases your speed by 1 level.
If an effect would normally cause the mount to fall prone, and it is travelling at a Canter or Gallop, it can instead have its speed reduced to a Walk instead of falling prone.

Changing Direction

When a mount attempts to change its direction it rolls a Dexterity check. It can up an amount up to the amount in the table below. Travelling a high speed imposes a penalty: -5 for a Canter, -10 for a Gallop.

Check       Turn

<5             Veer (45 degree turn)
5-9           Turn (90 degree turn)
10-14       Arc (135 degree turn)
15+          Spin (180 degree turn)

Verticality (Flying)

Directions: Dive (straight down), Dip (45 degrees downwards), Horizontal, Rise (45 degrees upwards), Climb (straight up)

While flying a mount attempts to change it's verticality, it must roll a Dexterity check. It can change its vertical direction up to a number of levels equal to the result of the check divided by 5 (rounded up). For each step up in verticality your speed decreases by one step, and for each step down in verticality your speed increases by 1 step. E.g. a 9 Dexterity check = can change from Galloping Horizontally to Climbing at a Trot.

 Special Maneuvers

Jump -- Jump over something. Travelling at a Gallop increases the mount's normal jump distance by 5 ft. If travelling over difficult terrain, the mount must make a DC 10 Dexterity check or fall prone when attempting to jump over something.

Collide -- run mount into / over something. Requires a DC 15 Animal Handling check, you have disadvantage on the check if the target is larger than your mount.

Close -- Get close to a target (such as a person, other mount, or vehicle, in prep for something). Requires DC 10 Dexterity check, and the target to be within 30 ft and travelling at the same speed and in the same direction as you.

Hover (Flying Only) -- Requires a DC 15 Strength check by the mount.

Quote from Agilemind >>

For mounts you also need to consider the mental state of the mount:

Mental State

Each time a mount or creature pulling a vehicle takes damage, they must make a DC 10 Wisdom saving throw. On a failure, they become panicked.  A  creature with fewer than half their maximum hit points or within 5ft of a panicked creature has disadvantage on the save. A panicked animal must attempt to increase its speed on each of its turns, and has disadvantage on ability checks to change direction or make maneuvers. A creature within 5ft of a panicked animal can use an action to make an Animal Handling check (DC 10) to calm it down, on a success they remove the panicked condition. 

Changing Speed

Speeds: Stop, Walk, Trot, Canter, Gallop

When the mount attempts to change it's speed it rolls a Strength check. It can change its speed up to a number of levels equal to the result of the check divided by 5 (rounded up). E.g. a 14 Strength check = can change from a Gallop to a Walk.

Moving through an area of difficult terrain automatically decreases your speed by 1 level.
If an effect would normally cause the mount to fall prone, and it is travelling at a Canter or Gallop, it can instead have its speed reduced to a Walk instead of falling prone.

Changing Direction

When a mount attempts to change its direction it rolls a Dexterity check. It can up an amount up to the amount in the table below. Travelling a high speed imposes a penalty: -5 for a Canter, -10 for a Gallop.

Check       Turn

<5             Veer (45 degree turn)
5-9           Turn (90 degree turn)
10-14       Arc (135 degree turn)
15+          Spin (180 degree turn)

Verticality (Flying)

Directions: Dive (straight down), Dip (45 degrees downwards), Horizontal, Rise (45 degrees upwards), Climb (straight up)

While flying a mount attempts to change it's verticality, it must roll a Dexterity check. It can change its vertical direction up to a number of levels equal to the result of the check divided by 5 (rounded up). For each step up in verticality your speed decreases by one step, and for each step down in verticality your speed increases by 1 step. E.g. a 9 Dexterity check = can change from Galloping Horizontally to Climbing at a Trot.

 Special Maneuvers

Jump -- Jump over something. Travelling at a Gallop increases the mount's normal jump distance by 5 ft. If travelling over difficult terrain, the mount must make a DC 10 Dexterity check or fall prone when attempting to jump over something.

Collide -- run mount into / over something. Requires a DC 15 Animal Handling check, you have disadvantage on the check if the target is larger than your mount.

Close -- Get close to a target (such as a person, other mount, or vehicle, in prep for something). Requires DC 10 Dexterity check, and the target to be within 30 ft and travelling at the same speed and in the same direction as you.

Hover (Flying Only) -- Requires a DC 15 Strength check by the mount.

 
This is very much the kind of stuff I was hoping to get. Thank you very much.

We have a small group of panic rules, but they are game standard, so I will introduce yours to the team toda and see what they say.

Speed we already account for (and we have both difficult terrain and unstable terrain, so we can reduce by half and one quarter). What we call a "shift" you add an interesting animal's strength roll here. With the buildup of fatigue, that creates an interesting effect. I like that, and may use fiat, lol.

This part I truly love, as it is the kind of thing we are going for.:

When a mount attempts to change its direction it rolls a Dexterity check. It can up an amount up to the amount in the table below. Travelling a high speed imposes a penalty: -5 for a Canter, -10 for a Gallop.

Check       Turn

<5             Veer (45 degree turn)
5-9           Turn (90 degree turn)
10-14       Arc (135 degree turn)
15+          Spin (180 degree turn)

I love your terminology for it. We are only using three turns through 90 degrees, but that came from the Vehicle rules, and this is a really nice little set up, so imma steal it.  Thank you!

I note you are using a DC 15 for the most part, with a 10 for some of the less involved ones.

This is one of the most creative things I've seen:

It can change its vertical direction up to a number of levels equal to the result of the check divided by 5 (rounded up). 

The thing that stands out to me is the introduction of chance in the "pull up, pull up" sense, meaning that even if success happens on the roll, there is still a chance there may be a collision, which is just super cool to me.

Delay the math a bit while narrating and you can build a quick moment of suspense, then make it seem like disaster, and then have the "top of the tower be broken" as they brush by, injuring the mount but making the getaway, lol.

(yes, I do indeed visualize every single mechanic I engage with in the game, lol).

I am going to introduce this at today's meeting -- I'm under a deadline for this section of my campaign, and while there isn't that kind of ting for the others, all of us have a need for this kind of thing (our players are excited after the last playtest of the vehicles rules).

Thank you.