Creative player used Command to suicide kill boss monster?

Question

We are brand new to D&D. Recently we finished up the first section of the starter set for 5E.

There was a point in the story where one of my PC's got really creative and wanted to cast Command out of combat (while sneaking) on a boss NPC, and then immediately command that boss to kill himself by shoving a javelin right into his head.

Since this was out of combat, and there were no turns, my player's rationale was that he could these things in succession since it was part the group narration, and just had to pass a difficulty check...

I felt this was too strong, and that I was probably missing something from the rules since I had only just bought this box the night before.

So as the DM I stepped in and said "no you can't do that... that can't be right, that's too strong." So I asked my player to roll a d20 to see if he was successful, which he was.

But I feel like I overstepped my bounds because I basically said "no" to my player because I didn't want this boss encounter to be bypassed so easily.

Was I in the wrong to try to stop my player from doing that crazy one hit kill?

How would this situation have played out if I had more experience with the rules?

Answer 1

I agree with Dan B's first point, but let's expand upon it.

1. The command is only a single word. "Suicide" could maybe work, though in my experience, it is rarely used as a verb . However...

2. As Dan mentioned, the command cannot be directly or obviously harmful to the target. Thus, "Suicide" or some one-word version of "stab self" would not work.

3. The Command only is followed for 1 round, or about 6 seconds. If you wanted to cause the target to do multiple things in succession, it would require several successful castings of the spell with different Commands to accomplish more intricate behaviors.

So, ultimately, you were right in your ruling. You cannot make a target do anything obviously harmful with Command.

Now, getting a target to APPROACH across a trap that he hasn't spotted... ;)

Answer 2

Command says: "The spell has no effect if... your command is directly harmful to the creature."

Also, even if a creature wanted to kill itself, 5e doesn't have rules for doing so in one attack. It would use the same rules as for attacking helpless creatures, meaning the attack has advantage and is an automatic critical. But you can't just say "he cuts his own throat and now he's dead"; hit points do not work that way.

Answer 3

The spell has no effect if the target is undead, if it doesn’t understand your language, or if your command is directly harmful to it.

In the rules for the spell, it says the creature cannot hurt itself. The spell would end after casting. Also don't argue with your players. You are the DM; Your job is to describe what happens, not discuss it. Your player absolutely can cast that spell and say any one word command. Tell him what happens. In this case, your player wasted a turn and a spell slot for no effect.

"As you finish casting your hand motions for the spell, you lock your mind on the target and whisper the final incantation needed to complete it: Suicide you say. For a moment the warrior stands perplexed, but then shakes his head, snapping back to reality and back to his senses." -DM

Some typical commands and their effects follow. You might issue a command other than one described here. If you do so, the DM determines how the target behaves. If the target can’t follow your command, the spell ends.

Suicide is a noun, not a verb, so it isn't a command. Using suicide as a command for this spell is just as confusing as someone using the word "Apple!" Explain to your player that he must use a command or the spell does not work, out of game of course. Game time is for playing. Discussion is for after.