Mounted combat question.

[tomjon]

Say you have a paladin mounted on a Pegasus. Now let’s say the mount wins initiative can the Pegasus Take a ready action move on the riders turn. If so how specific dose the ready move action need to be. Also can the rider interrupt the ready move action. Such as to attack, cast a spell or anything else.

One other question dose a flyby ability of let’s say a Peryton affect the rider also.

[BloodSnake'sCha]

What you wrote work only with uncontrolled mount.

If the mount with flyby is uncontrolled the rider in moved by forced movement which doesn't provoke attacks of opportunity.

[tomjon]

Ok thanks. Was thinking about the find greater steed that gives it at least a six intelligence. Never thought of it as forced movement.

[Chugger]

You need to ask your DM, and if you're DMing you need to decide how flyby and a rider works.

A DM could rule that flyby applies to the rider as well as the mount. A DM could rule it only applies to the mount, that the mount knows a special skill to avoid OA that the rider doesn't know. I think the first one is more "logical" and the second one offers more "game balance" (because a rider that has flyby is pretty powerful).

[BloodSnake'sCha]

Ok thanks. Was thinking about the find greater steed that gives it at least a six intelligence. Never thought of it as forced movement.

Look closely on the difference between find steed and find greater steed.

Greater steed

You control the mount in combat. While the mount is within 1 mile of you, you can communicate with it telepathically. While mounted on it, you can make any spell you cast that targets only you also target the mount.

You are forced to control a greater steed.

This line was changed for find steed in some errata

Your steed serves you as a mount, both in combat and out, and you have an instinctive bond with it that allows you to fight as a seamless unit. While mounted on your steed, you can make any spell you cast that targets only you also target your steed.

RAW, a mount from find steed can be uncontrolled but a mount from find greater steed can't be uncontrolled (you are forced to control it).

[Zhorn]

You are forced to control a greater steed.
Are you sure that's what it means?
It could be "you as the caster control the actions of the summon creature" as opposed to a regular mount which would be in the DM's control in play when not being directed by the rider as a controlled mount.
It wouldn't be the first pitfall to pop up from commonly used words being the same as wording used in rules language.

It would also be rather silly to have a higher level version of the spell be the more restricted.

For what it's worth for RAI
Dragon Talk titled Sage Advice on Mounted Combat Jeremy Crawford explained the intended rules
https://www.youtube.com/watch?v=99tX6tmc73Q&feature=youtu.be&t=33m39s
and

https://twitter.com/JeremyECrawford/status/970111071955464198
Find steed / find greater steed—when you ride the mount in combat, you decide whether it follows the rules for a controlled or an independent mount

[BloodSnake'sCha]

Are you sure that's what it means?
It could be "you as the caster control the actions of the summon creature" as opposed to a regular mount which would be in the DM's control in play when not being directed by the rider as a controlled mount.
It wouldn't be the first pitfall to pop up from commonly used words being the same as wording used in rules language.

It would also be rather silly to have a higher level version of the spell be the more restricted.

For what it's worth for RAI
Dragon Talk titled Sage Advice on Mounted Combat Jeremy Crawford explained the intended rules
https://www.youtube.com/watch?v=99tX6tmc73Q&feature=youtu.be&t=33m39s
and

I agree that it is RAI, I even noted there was an Errata(can't find it, I just remember it) that changed find steed but not find greater steed for some unknown reason (probably because they are from different books).
I can even tell you that some DM rule that the mount from fund steed most be controlled because that what find greater steed says.

[Zhorn]

If the mount with flyby is uncontrolled the rider in moved by forced movement which doesn't provoke attacks of opportunity.

A DM could rule that flyby applies to the rider as well as the mount. A DM could rule it only applies to the mount, that the mount knows a special skill to avoid OA that the rider doesn't know.
In this case I'd say BloodSnake'sCha has the general RAW covered.

Opportunity Attacks
...
You also donÂ’t provoke an opportunity attack when you teleport or when someone or something moves you without using your movement, action, or reaction.
...
The only way by RAW that you are a target for Opportunity attacks resulting from your mount's movement is if they have triggered said opportunity attack.

Controlling a Mount
...
if the mount provokes an opportunity attack while you are on it, the attacker can target you or the mount.
Peryton's flyby means they won't trigger an opportunity attack from leaving an enemies reach, so by the extension of forced movement it will cover the rider also.


I can even tell you that some DM rule that the mount from fund steed most be controlled because that what find greater steed says.Good thing you now have a reference from the designers should such a silly ruling pop up at your tables ever again.
Generally I like to back up the 'DM is right' at their own tables, but I always hold the caveat of 'but it needs to make sense.
Apply more restrictions to Find Greater Steed than for Find Steed?
I'd still go along with their choice, but I point out that it's a silly ruling, and cite the references outside game time.