What is the extent of the commands a Cambion can issue through Fiendish Charm?

Question

In the last session we played, our DM sent Cambions at us. One of them managed to land a Fiendish Charm on our Barbarian and commanded him to attack our Bard. The part of text about issuing commands is quite short and reads as follows:

The charmed target obeys the cambion's spoken commands.

The DM said that the charmed target has to obey the commands "as best as he can", thus the Barbarian proceeded to quite literally demolish our Bard with two (regular one + Extra Attack) greatsword attacks empowered with Great Weapon Master, while raging. We felt kind of overwhelmed.

Is Fiendish Charm really that strong? Do you have to obey the issued commands with literally all you have, feats and other power-ups included?

Answer 1

Yes, it is strong and they must obey the order, unless it's suicidal - then they get another save to resist.

While the target is charmed per the condition as part of the ability, it is the information after that line that defines how the ability is applied:

The charmed target obeys the cambion's spoken commands. If the target suffers any harm from the cambion or another creature or receives a suicidal command from the cambion, the target can repeat the saving throw, ending the effect on itself on a success.

The target must obey; should that order be suicidal, the target gets another save to resist the order. See this question regarding failing a save to resist a suicidal command.

Interpretation of Extent of Obey

This is where things leave the realm of RAW and are up for interpretation. To the extent of best of their ability is not stated in any rules. Using the instruction given, "Attack the bard!" There are a few ways to go about it. This list is not exhaustive.

1. Follow the instruction exactly as commanded. Attack once as that was all he was instructed to do.
2. Attack as he would regularly do, if making extra attack is normal that's what he does. He does not expend magical or other resources unless they are part of what he normally does as an attack.
3. Go all out using any magical items or abilities that he has to do as much damage as possible.

Option 2 is the middle ground, the one I use in my games and the option that has come up in most games I've played in, but ultimately it's up to the DM to make the final ruling, ideally keeping in mind that what applies to players should equally apply to monsters.

Answer 2

As the other answers have stated, the charmed barbarian must follow the instructions of the cambion so long as the instruction is not suicidal (at which point they get to repeat the saving throw and potentially break the charm, after which they don't have to do anything the cambion says):

Fiendish Charm. [...] The charmed target obeys the cambion’s spoken commands. If the target suffers any harm from the cambion or another creature or receives a suicidal command from the cambion, the target can repeat the saving throw, ending the effect on itself on a success.

However, exactly how the instruction is carried out is up to the DM, as no further guidance is given from the Fiendish Charm text.

However, your DM may be ruling that the barbarian must follow to the best of his abilities based on a similar effect, the dominate person spell:

While the target is charmed, you have a telepathic link with it as long as the two of you are on the same plane of existence. You can use this telepathic link to issue commands to the creature while you are conscious (no action required), which it does its best to obey.

The Fiendish Charm text does not say this explicitly, but since it doesn't give any guidance on how the charmed barbarian should obey the command, this seems like a reasonable ruling to make.

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Depending on how your DM handles characters who are not in control of themselves, then as @NautArch points out, this could prove to be an interesting roleplay opportunity.

If your DM takes control of that character (or at least their decisions) until the charm is broken, then this is a moot point, but if you are free to roleplay your character with the restriction that you think this cambion is now your best friend and you want to do anything they say, you could roll with it rather than look for ways to metagame around it.

At that point, it might then be by your choice rather than the DM's that you decide to rage and use Great Weapon Master, to really try to put this bard down. Anything to help your new best friend, right? Your DM might even award inspiration for good roleplaying. Once the charm is broken, your character will then be free to do whatever they would normally do, maybe try to help undo the damage they just did or (more likely for a barbarian) just teach that cambion a lesson for controlling him.

Of course, with any mind control ability or similar, there is a fine line to walk regarding fun roleplay vs. taking away player agency, at which point it might be better for the DM to simple temporarily control that PC until they are no longer charmed. It all depends on your table.

Answer 3

Yes, the barbarian does have to obey.

As best he can however was added by the DM and even then, it means that, to the best of his ability, the barbarian will attempt to do exactly the spoken command as verbatim as possible. For example, if the barbarian needs to climb a wall to reach the bard, then he will do so. He has to do his best to go attack the bard, after all, because that was the command.

What "as best he can" doesn't mean is that the barbarian will not only do his best to successfully try to perform the command, but also do it in the best way possible to do so, going even beyond what the stated command said.

The barbarian will do his best to be able to do exactly what the command said: attack. Yes. But doing the attack the most powerful and best way that he can, not necessarily. Probably "attack the bard" could be interpreted as "simply attacking" that the bard, attacking like the barbarian usually attacks.

• Example: if the barbarian is in the habit of doing all the attacks he can, but not raging unless the situation seems serious, then as the barbarian knows he's much stronger than the bard, he'd do his two attacks, but without raging.

  If the monster had commanded "Attack the bard to the best of your abilities with all the power you have!" then yeah, barbarian would have to do his best to go nuclear on the bard.

But the other side of the medal is that the barbarian could say: "ok, so I just throw a rock at the bard, not even putting all my strength in it, too, for a whopping 1 damage! There, I have fulfilled the condition for the command!"

Obviously that would be a little bit of cheaty "interpretation" on the part of the player.

So, as per RAW, there always will need to have some DM call being made for such commands.

For example, if the DM determines that the charm is essentially word-based, then a literal interpretation of the command by the barbarian would work ok. Throw that puny rock! But if the DM determines that the charm is more like some kind of mind-control effect instead, then yeah it figures that the barbarian would attack with all his ferocity: he'd be obeying the actual intent of the Cambion, then, not just his words.

Now, even with 100% mind control, the mind control can be either Cambion-knowledge dependent, or not. If the command is Cambion-knowledge dependent, then it depends on what the Cambion actually knows or can guess about the barbarian. If the Cambion does not know that the barbarian can Rage, then the barbarian can get away with just doing the most ferocious "normal" attack can.

If the command is instead mentally all-pervasive, like actually temporarily turning the barbarian super-evil with only one goal in mind: "kill the bard ASAP!", then yeah even if the Cambion doesn't know that the currently battleaxe holding barbarian also has hidden in his backpack a super-costly magical bomb able to deal 9999 dg + save vs Disintegrate DC 30 vs a single target, that he keeps "for a really bad fight", the barbarian would not only rage, but make one less attack with his battleaxe, in order to draw the infamous bomb and proceed to really finish off the bard with the bomb.

So it really greatly depends on the DM's ruling of how "strong" that particular enchantment is here.

Since the DM just made the rolepaying description of the command quite boring and simple, only 3 words "Attack the bard!", I would have just forced the barbarian to attack like he normally does in fights. Forcing an enchanted PC to go all nuclear on an ally, require a bit more "dread and oomph" from the verbal description, like the DM saying this around the table:

Instead of simply:

"The Cambion then says: 'Attack the bard!'"

It could have been this description instead:

"The Cambion then says: 'Attack the bard!'. Suddenly the barbarian feels his mind reeling and stopping being his own. This is not a simple charm spell enchantment here, but a demonic-powered one! Everybody easily sees that the barbarian's face is now filled with extreme hatred, his spirit now controlled by pure evil. He now hates the bard with all his guts and obviously has only one goal: attack the bard, in the most powerful and violent way possible!"

The players would have had an intense situation, without the lash-back of ending up thinking that the extreme attack was too "DM-forced", but instead the natural result of the way that charm seemed to work.

But since the DM specified that the barbarian must do the attack to the best of his power, then that is what happens and the player really had no choice, despite the loss of agency.