Mounted Combat - Specifics for this turn

Question

I have a level 8 paladin, mounted combatant feat, who will be riding a celestial warhorse via find steed. As level 8, my paladin gets 2 attacks per round. The horse will be fitted with horseshoes of speed, so move of 90.

The example turn I'm considering is the following. The horse moves 30', where I deliver a blow to a creature with a lance, then moves another 60' where I hit with the lance again against a second target. Regardless of if I intend to close to melee, can the horse use the trampling charge feature during one or the other of these attack events? When I move away from the first target, do I invite an attack of opportunity?

I've done some research about mounted combat, and the information I've seen seems to say that a mount must be acting independently in order to use the attack action. A warhorse obtained by the paladin spell find steed has a telepathic link and an intelligence of 6. Is it reasonable that the paladin is working in concert with the horse telepathically to arrange attacks and allowing the horse to execute the orders, "charge the orc ahead of us, then keep moving to the bugbear to the left"...

Specifically, I'm asking if the example turn reflects a correct understanding of the mounted combat rules, and I want to know about how mount attacks and attacks of opportunity work.

Answer 1

The example turn you described is legal concerning RAW. You would be able to break up your movement and attack both targets as long as your mount has enough movement to get you there. As for the opportunity attack, any time you move outside of a creature's reach without taking the Disengage action you would provoke an attack of opportunity. Luckily, in your example you are using a lance which has the Reach tag. This means that unless the creature you are attacking also has a reach weapon or has some other way to extend its melee reach to at least 10 feet you could choose not to provoke an opportunity attack simply by attacking within your reach and staying outside of theirs.

If for some reason avoiding the opponent's reach cannot be done, let's consider the following:

Page 198 of the PHB:

if the mount provokes an opportunity attack while you’re on it, the attacker can target you or the mount.

That being said, the mount can use it's action to take the Disengage action to avoid being attacked,

The initiative of a controlled mount changes to match yours when you mount it. It moves as you direct it, and it has only three action options: Dash, Disengage, and Dodge.

and you would not provoke an opportunity attack because,

Page 195 of the PHB:

You also don’t provoke an opportunity attack when you teleport or when someone or something moves you without using your movement, action, or reaction.

As for the mount's ability to attack...

Although the steed has an unusually high Intelligence of 6, that doesn't make the mount an intelligent creature who can act independently of you, and it can't attack while ridden. Here's a couple links to a few Tweets from Jeremy Crawford, one of the lead game designers:

Not Independent.

The mount summoned by the find steed spell serves the summoner. It isn't an independent creature.

Still has normal mounted combat options

While ridden, the steed follows the normal mounted combat rules (PH, 198). Unridden, it has normal action options.

The normal mounted combat rules state that a mount not acting independently can only use the Dash, Disengage, and Dodge actions as shown in the quote above in bold.

For trampling charge to work, the mount would need to use the Attack action to attack with its hooves, which isn't in the set of the controlled mount's possible actions.

Trampling Charge. If the horse moves at least 20 feet straight toward a creature right before hitting it with a hooves attack, ...

Therefore, the mount cannot use trampling charge.

Answer 2

First of all (PHB p.198):

Intelligent creatures, such as dragons, act independently.

Now your mount is as intelligent as a Young White Dragon so this probably applies to it (check with your DM).

As such the mount acts on its own turn and can take the attack action to trample; with your telepathic link you can ask your mount to do something, however, what your mount does is up to it (as an NPC); given that you "fight as a seamless unit", your DM would need a pretty good reason for doing something different.

Notwithstanding, while an independent mount is having its turn, it is not your turn! You action (and any bonus action) happens on your turn, not its, and so you can either take the attack action and attack creatures that are currently within your reach when your turn happens or take the ready action to attack once (since multiple attacks require the attack action and you are taking the ready action) on your mount's turn as you ride by someone.

As an alternative, you could get your mount to take the Ready action in order to move on your turn. You could then do as you describe but both you and the mount would provoke opportunity attacks because the mount has taken the Ready action, not the Disengage action. Similarly, it could not Attack.

If your DM is kind and allows you to control the mount then you can do as you have described. However, your mount can only take the Dash, Disengage or Dodge action; it cannot attack. If it takes the Disengage then its movement does not provoke opportunity attacks for either it or you.