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.
Best Answer
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:
That being said, the mount can use it's action to take the Disengage action to avoid being attacked,
and you would not provoke an opportunity attack because,
Page 195 of the PHB:
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.
Still has normal mounted combat 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.
Therefore, the mount cannot use trampling charge.