Consider the following example:

Character A, Character B, and Character C are in one room. Character A is an eladrin (MToF p. 62) of 3rd level or higher. C is a succubus.

Characters A and B are allied. C is a foe.

First, C charms B (using the succubus' Charm action), and tells B to attack A.

Then, A charms C (using the autumn eladrin's Fey Step), and convinces C to stop attacking. (He also tries to charm B with this ability, but B succeeds on the Wisdom save.)

No other intervening events occur. Is B going to attack A?

C (the succubus) can't directly attack A (the eladrin), but C's previous command to B still stands

The charmed condition on its own is pretty limited in what it does:

• A charmed creature can't attack the charmer or target the charmer
  with harmful abilities or magical effects.


• The charmer has advantage on any ability check to interact socially
  with the creature.

The succubus' Charm action is more specific (emphasis mine):

Charm. One humanoid the fiend can see within 30 feet of it must succeed on a DC 15 Wisdom saving throw or be magically charmed for 1 day. The charmed target obeys the fiend's verbal or telepathic commands. If the target suffers any harm or receives a suicidal command, it can repeat the saving throw, ending the effect on a success. If the target successfully saves against the effect, or if the effect on it ends, the target is immune to this fiend's Charm for the next 24 hours.

The fiend can have only one target charmed at a time. If it charms another, the effect on the previous target ends.

If a succubus charms a creature and it fails the Wisdom save, it must obey the succubus's verbal or telepathic commands. The only exceptions are if it suffers any direct harm or receives a suicidal command (such as to throw itself into lava), in which case it can repeat the save. If the succubus commands a charmed target to attack an ally, the charmed target follows that order.

The succubus (C) can Charm B, and then (assuming B fails the save) command B to attack A. So far, so good.

Then, we look at the eladrin's Fey Step feature (MToF, p. 62):

As a bonus action, you can magically teleport up to 30 feet to an unoccupied space you can see. Once you use this trait, you can’t do so again until you finish a short or long rest.

When you reach 3rd level, your Fey Step gains an additional effect based on your season; if the effect requires a saving throw, the DC equals 8 + your proficiency bonus + your Charisma modifier:

Autumn. Immediately after you use your Fey Step, up to two creatures of your choice that you can see within 10 feet of you must succeed on a Wisdom saving throw or be charmed by you for 1 minute, or until you or your companions deal any damage to it.

Unlike the succubus, the autumn eladrin's Fey Step simply imposes the charmed condition on a failed save, with no additional effects. Nothing about the condition forces the charmed target to obey the eladrin's orders in general. The charmed target simply can't harm the eladrin directly, and the eladrin has advantage on social interaction checks against the charmed target (e.g. Persuasion, Intimidation, Deception, or other Charisma checks not associated with specific skills).

The eladrin (A) can use Fey Step to teleport within 10 feet of the succubus (C), then attempt to charm it; if the succubus fails the save, then it is charmed by the eladrin. This prevents the succubus from directly attacking the eladrin.

However, nothing about this situation on its own affects the succubus' previous command to B, who is still charmed by the succubus - so if nothing else is done, B will still attack A (the eladrin) on A's turn. A could attempt to convince C (the succubus) to tell B to stop attacking, but there is no guarantee of success.

As C is an enemy monster, A's Charisma check (at advantage) would be made against a fixed DC; given that the two sides were previously in combat, it would likely still be quite difficult to convince the succubus to call off the attack.

Of course, the DM might decide that the charmed condition does provide some magical encouragement for the charmed target to find the charmer's demands more appealing, and so they might decide to set a less extreme DC for the check. In other words, it might be normally impossible to convince an enemy that's actively fighting you of something, but the charmed condition, in principle, makes them treat you as less of an active enemy - at the least, they can't attack you directly, and they're receptive to what you have to say - so that might make it possible (even if still difficult) to convince them of that thing.

B attacks A

The Succubus' Charm action does more than just create the Charmed condition:

The charmed target obeys the fiend's verbal or telepathic commands.

The target (B) has been given a command - that command remains in effect until the Charm effect ends or the Succubus issues a new command. The Charm ends after 24 hours or if B passes a saving throw and in no other way - not the Succubus being Charmed by someone else or even dying.

The Charmed condition does the following:

• A charmed creature can't attack the charmer or target the charmer with harmful abilities or magical effects.


• The charmer has advantage on any ability check to interact socially with the creature.

Nothing there stops the succubus from ordering B to attack A - it is not an attack by the succubus, not a harmful ability and not a magical request: it's just a request to an ally, albeit a magically compelled ally. Some GMs may rule that it does prevent such an order, but even so, it would not terminate an order that had already been given.

It really depends on how you read the Charmed condition:

A charmed creature can't attack the charmer or target the charmer with harmful abilities or magical effects.

Does ordering someone else to kill someone count as "attacking them"? In plain English, yes; in D&D, maybe. It isn't an "Attack" -- you don't roll a d20 against their AC.

In addition, "target the charmer with harmful abilities or magical effects" could even apply here. If we take "Target" loosely, magically telling B to attack A is "Target"ing A with a magical effect that is harmful to B (telepathic control of A).

If ordering someone else to kill them is an attack, then the succubus cannot order B to attack A. I'd argue if it is an attack, "letting an existing attack continue by doing nothing" is also an attack, so the Succubus would have to tell B to stop attacking A.

However the Succubus may not have time to revoke her order on B even in this case, and B will continue to attack A until the Succubus can get around to it.

On the other hand, if you take the narrow interpretation, then the a charmed target is free to order familiars, summons, allies, or charmed targets to attack the source of the charm effect. And the succubus is not restrained by the charm.

This narrow definition would even permit you to cast a fireball adjacent to the being who charmed you. A fireball is not an attack, and its target is the location not the creatures in the blast radius.

Overall, using the narrow definition of "target" and "attack" on the Charmed condition leads to pretty ridiculous results.

Using the plain English interpretation leads to a reasonable result -- someone Charmed cannot use abilities or magical effects or willingly cause attacks under their power to harm the Charmer. And no more fireball-sized loopholes.

This is backed by Jeremy Crawford, who in effect says:

5e has a slimmer definition of 'target' when compared to 4e. Target means, in game, what it means in English. ("If the rules do not specifically add or change the meaning in a significant way, the word means what it means in regular idiomatic English"). So target means: someone or something is chosen to be affected by the ability.

The Succubus is using magical effects to target and harm the Charmer.

A core part of this it that many Charm effects have extra effects on top of the Charmed condition, but the Eladrin Autumn teleport effect does not.

Now, as an aside, the Eladrin can charm two targets as part of her Fey Step; so it could try to charm both the Succubus and B. If successfully charmed, B would no longer attack A even though C orders her to.