D&D 5E Toll the Chest

[iserith]

I roll the save for the mimic. If it saves, there is no damage and the PCs are none the wiser. If it fails, it takes damage, reacting and the PCs have revealed the mimic.

By rolling a saving throw, even if it succeeds, the players may now be aware that the chest is a creature since only a valid target need make a saving throw. Is it a problem at your table that the players then act on that information and attack?

 

[DND_Reborn]

By rolling a saving throw, even if it succeeds, the players may now be aware that the chest is a creature since only a valid target need make a saving throw. Is it a problem at your table that the players then act on that information and attack?

But if it makes the save, how do they know? Perhaps the spell failed to do anything because it is a chest?

Let me put it this way:

Player: I cast toll the dead on the chest in case it is a mimic.
DM: (rolls d20 behind screen) Nothing happens.
Player: AHA! He rolled a save, it is a creature! We attack!!!

OR

Player: I cast toll the dead on the chest in case it is a mimic.
DM: Nothing happens.
Player: Guess it is just a chest and my spell didn't work on it.

Does the die roll indicate something is going on to the character? Of course not.

OF COURSE... here's the thing: toll the dead is a cantrip. The PC can cast it 5 or 6 times if they want. If the mimic makes all those saves... well, they think it's a chest. If it is a chest, the spell never has any affect on it and, well, they still think it's a chest. But, if it fails a save, now it takes damage and reacts visibly to being "injured" and they will likely know its a mimic...

 

[iserith]

Player: I cast toll the dead on the chest in case it is a mimic.
DM: (rolls d20 behind screen) Nothing happens.
Player: AHA! He rolled a save, it is a creature! We attack!!!

A player could, after watching you roll a die behind the screen and suspecting it is in fact a mimic because you rolled, just loose an arrow into the chest. Is that an issue?

 

[DND_Reborn]

A player could, after watching you roll a die behind the screen and suspecting it is in fact a mimic because you rolled, just loose an arrow into the chest. Is that an issue?

No, but they could loose an arrow at the chest whether it is a chest, a mimic, or suspect it is trapped in some other fashion, whether someone casts a cantrip on it before hand or not.

And, FWIW, I roll erroneous dice behind the screen all the time... so my players know it doesn't necessarily mean anything when I do.

 

[iserith]

No, but they could loose an arrow at the chest whether it is a chest, a mimic, or suspect it is trapped in some other fashion, whether someone casts a cantrip on it before hand or not.

And, FWIW, I roll erroneous dice behind the screen all the time... so my players know it doesn't necessarily mean anything when I do.

Right, so as long as they don't tip anyone off that they're attacking the chest because you rolled a save, then it's all good.

 

[DND_Reborn]

Right, so as long as they don't tip anyone off that they're attacking the chest because you rolled a save, then it's all good.

Sure. In my games when players suspect something like this shooting an arrow, poking it with ye ol' 10-foot pole, etc. to reveal a trap is pretty common.

The characters have reason to think something is wrong, and should explore it however they can. The issue at hand has been more whether failing a mental save (especially) would have an visual effect to cue the players the chest is, in fact, a mimic. IMO, it doesn't. Others have expressed it should.

I would also be for supporting a perception check, etc. to allow them to notice the successful save in some fashion.

 

[James Gasik]

Maybe we're taking the wrong tack here. What actions, could players take, if they suspect something to be a monster in disguise, would prevent them from being surprised by it?

As I asked upthread, is the Mimic just always supposed to surprise the party because they have "no way" to know it's a Mimic?

Because so far, perception checks, investigation checks, outright attacking it, and forcing it to make saving throws have all been rejected at one point or another.

 

[DND_Reborn]

What actions, could players take, if they suspect something to be a monster in disguise, would prevent them from being surprised by it?

Take the Ready action to respond (attack, cast, whatever) if the chest moves, attacks, etc.

But, when I DM, if the PCs expect something to happen, it is VERY hard to actually get "surprise" on them.

Because so far, perception checks, investigation checks, outright attacking it, and forcing it to make saving throws have all been rejected at one point or another.

While I can't speak for others:

Perception checks I recommended
Investigation checks I never mentioned but sure, works the same (in essence) as Perception
Attacking it I actually said was viable
Saving throws (if it fails) would work IMO

So... I guess I'll have to leave it up to the others who don't find any of those acceptable to answer further.

 

[jgsugden]

If your PCs suspect it is a mimic and are going to do something to test their theory, worrying about the fine details of how they test it is a waste of time and a bad idea. The jig is up. When the player announces the intent to cast Toll the Dead, I'd roll the save and say, "As you cast the spell the chest sprouts a gigantic psuedopod and starrts to wobble towards you. It rolls an X on the save."

If you tell them they can't cast the spell unless they know it is a creature, then they'll just test it another way. If you tell them that it either isn't a creature, or it made the save, they'll test it another way. Once they suspect, most of the time the PCs will just test it out one way or another.

This is why I make sure that I put mimics in places that people are too busy to suspect. For example: In the Forge of Fury module there is a bridge. I places a wooden platform on the Roll20 map on each side of the bridge. PCs stepped on the platforms to get on and off the bridge - except the one on the far side was a mimic. The PCs were so occupied by the other creatures in the room that they never suspected the platofrm might be a mimic, trap or anything else. It turned the fight into something interesting, especially as it dragged the caught barbarian down into the pit so that if the barbarian broke free, they'd drop into what was beneath the bridge. Other great mimics have been a door in an open door (so that it can go after the last PC in the group to go through the door), a rope hanging from a ceiling that PCs might use to swing across a ravine, and a personal favorite - the mimic was the plug that was a clay plug that was holding back water that would otherwise flood into a room. The PCs saw it crack and ran to secure it ... resulting in the mimic sticking to the wall next to the hole, flooding back the PCs and taking on one PC that it was holding in the way of the blasting water. The Mimic was no threat to that 7th level party, but it did create chaos as it announced their presence to the bad guys in the lair and separated them briefly.

Historically, given the AC, speed and other features of the mimic, if they suspect something is a mimic - and it is - I'll ask them their tactics and often bypass the combat entirely if they're just going to obliterate it before it can approach.

 

[Maxperson]

It's bizarre that you continue to fail to understand my actual position. I trust this isn't deliberate on your part, so I'm going to go through the steps of play as I see this encounter playing out to give you a chance to catch up in your understanding of what I'm actually saying:

1. The party, not trying to be stealthy as they travel, comes within sighting distance of the mimic which notices them immediately.​

2. Because the mimic is trying to use its False Appearance ability, the DM determines whether or not it succeeds at remaining motionless. Of course, the DM can just decide it succeeds, but I would have it make a Dexterity (Stealth) check contested by the passive Perception scores of any members of the party who are keeping watch for hidden threats. Either way, according to the scenario described in the OP, it succeeds, and the DM describes to the players only that the party sees what looks to be an ordinary chest.​

3. The players, despite any suspicions they may have about the "chest", state that the party enters the room, approaching within 15 feet (one move) of the mimic.​

4. The player of the cleric states they cast toll the dead at the "chest".​

5. Because combat is beginning in order to resolve the cleric's action, the DM determines who might be surprised. Because the party was not trying to be stealthy, the mimic noticed them in Step 1 and is not surprised. Because the mimic succeeded in using its False Appearance ability in Step 2, the party did not notice the mimic, and they are surprised.​

6. The DM figures out where everyone is in relation to each other and to the mimic.​

7. The DM calls for initiative, which is rolled by all the participants.​

8. In round one, the party is surprised on their turns (see Step 5), and the mimic moves in and attacks them.​

9. In round two, all the participants take their turns in initiative order, including the cleric who can now cast the spell they declared in Step 4 at the mimic.​

I hope that clears things up a little.

It does, but it's not accurate in my opinion. I'm making alterations in bold below.

1. The party, not trying to be stealthy as they travel, comes within sighting distance of the mimic which notices them immediately.
2. Because the mimic is trying to use its False Appearance ability, the DM determines whether or not it succeeds at remaining motionless. Of course, the DM can just decide it succeeds, but I would have it make a Dexterity (Stealth) check contested by the passive Perception scores of any members of the party who are keeping watch for hidden threats. Either way, according to the scenario described in the OP, it succeeds, and the DM describes to the players only that the party sees what looks to be an ordinary chest.
3. The players, despite any suspicions they may have about the "chest", state that the party enters the room, approaching within 15 feet (one move) of the mimic.
4. The player of the cleric states they cast toll the dead at the "chest".
5. Because combat is beginning in order to resolve the cleric's action, the DM determines who might be surprised. Because the Mimic has no way to know combat has started and is waiting for the party to come close, it is surprised by the Spell. The party cannot be surprised, because it aware of the potential threat the chest poses.
6. The DM figures out where everyone is in relation to each other and to the mimic.
7. The DM calls for initiative, which is rolled by all the participants.
8. In round one, the Mimic is surprised Its turn (see Step 5), and the party may or may not move in to attack it, because if it saved against the spell, the party wouldn't know it is in combat, either.
9. In round two, all the participants take their turns in initiative order, including the cleric who can now cast the spell they declared in Step 4 at the mimic.