“Empty” is pretty contextual.

you have them roll for perception first then you are narrating the area and having players say what they want to do afterwards

now their actions are going to be influenced by their low perception roll

You shouldn’t be rolling for perception first. Players don’t get to roll until they actually do a thing, until then you use passive perception. And even if you are rolling a perception check on their behalf, you do it behind the screen. So they won’t know if they rolled well or not.

rolls come after the declaration of actions

Hard agree! But passive perception isn’t an action or a roll. It’s passive.

The thing about BAD traps versus a GOOD traps, though, is ensuring that players have the opportunity to try avoiding it.

Exactly. The players should have the opportunity to avoid it. If traps are only a binary - perfectly obvious or completely invisible depending on a single roll - then the characters had a chance to avoid the trap, but the player didn’t. And then “optimal play” is painstakingly triple-searching every square foot of the dungeon in case Schodinger’s Trap is lurking somewhere.

Which is either trivial and tedious (in games where you don’t track the passage of time) or stupidly punishing and tedious (if you are tracking time). Since I do prefer to track time spent, I’d rather give my players the sense that they can ‘logic out’ where traps are likely to be and encourage them to spend their valuable time searching only when and where it makes the most sense. After all, skill expression is a very rewarding part of playing a game. And being able to predict where a trap is likely to be and then finding one there? That really makes players feel like adventurers.

while the mimic remain motionless

Lesson one: not standing up.

“The room appears to be empty” when it actually is.

You shouldn’t be rolling for perception first. Players don’t get to roll until they actually do a thing, until then you use passive perception. And even if you are rolling a perception check on their behalf, you do it behind the screen. So they won’t know if they rolled well or not.

Yea, that was kind my whole point. The way you described earlier.

Traps are puzzles. Even if they didn’t roll high enough, you should still describe enough about their environment that they could reasonably deduce that a trap was there.

literally states to roll first then narratively describe after so they can deduce that a trap was there if the roll was low, which is what I was arguing against. That explanation has the order of events all wrong. Also, this goes back to the original point that players dislike when you roll for them behind the screen. Before the rules officially allowed it, many players would throw a fit about not being able to see the rolls.

Plus, I never mentioned passives. Disliked the concept so I don’t use them to begin with. I have only ever been talking about directly making rolls.

.

It seems to me the confusion lies in, what I would say is, an over-reliance on the grid in that you aren’t understanding my method, fundamentally, as you’re assuming the grid is being used when it isn’t. Your rebuttal is focused on having players be allowed to basically play Minesweeper with the grid, tediously wasting everyone’s time, when that would never be allowed as an option for them with how I do things.

For me, the grid only gets used for combat and nothing else. This way I never have to deal with players wasting time trying to cheese the game by asking to check every square because it’s all theater-of-the-mind, there is no grid. I might use visual help to display a room layout, but it’s only there for general reference. Players still get to try and predict where traps are and stuff based on my descriptions; they just tell me what part of my description they are interacting with, or if it’s just a general search of the room itself. Based on their input and how detailed they are, I then determine who needs to roll what, add bonuses and negatives if applicable, then the scene will play out.

Plus, this also allows me to keep track of time by treating each scene as 1 time block. I just jot down how long the entire scene took, then how long it took to travel to the next scene.

I had a DM make the entire house a mimic once. We spent like 6 turns of combat fighting a rug before we realized that was just the tongue.

…Sorry, you’re acting smug, but I’m not sure what you’re even trying to say. Did you not read my comment? Mimics breathe. Breathing causes motion. Ergo, they aren’t motionless. If you can spot the motion, you can distinguish them from a regular item. If not, you can’t.

Hit the uvula!

Relevant scene: Monster House, 2006

Edit: it was a girl House for the record

My dude, I take your point, but you’re writing in properties for the mimic that aren’t in the rules, based on your real world perception of how things work. That isn’t applicable to the game mechanics. If you really have to have something to wrap your head around to explain the mimic both breathing and being imperceptible while impersonating an object, then model mimic breathing as some form of motionless skin breathing. Just realise that when you go digging for another reason to say why you can see it happening, its your model that is wrong, not the rules.

…you’re writing in properties for the mimic that aren’t in the rules…

The rules don’t say goblins breathe, either. If you can’t extrapolate that living creatures breathe, you’re not doing a good job.

…to explain the mimic both breathing and being imperceptible

I’m quite clearly doing the opposite, though. As does the lore attached to it, which clearly says “a mimic in its altered form is nearly unrecognizable”. Nearly unrecognizable means it is recognizable.

…some form of motionless skin breathing.

Okay, now you’re the one writing in properties that aren’t in the rules. Especially since its skin can be just wood.

…its your model that is wrong, not the rules.

No, neither are wrong. You just misunderstood the rules. And my model. The rules say they are indistinguishable when motionless. I say they aren’t motionless. No contradiction.

There was a necromancer tower in an early issue of Dungeon magazine. It had a stairwell with broken stairs and debris. A mimic had replaced one of the broken stairs. The only possible clue is the fact that there’s more rubble than there are missing stairs.

Couldn’t the mimics just hold their breath for a long time? I also see no problem with them having a physiology so different that their body literally doesn’t move when they breathe, but I don’t play D&D, so maybe I’m missing something with that.

“You see nothing of note”

Breathing doesn’t guarantee that you can see something lol. Show me a breathing insect with its “chest” moving up and down. If you account for evolution then mimics who could best hide their breathing are also absolutely something that would happen. Plenty of mammals can hold their breath underwater a crazy amount of time. A mimic that could also position and shape its body would have no trouble hiding its breathing.

They’re motionless and indistinguishable and you’re just going to have to deal with that.

Bonus: the way to find them out would be to see if a character notices them looking out of place. Maybe it’s a contested stealth vs incestigation/perception role, or maybe the description of the room even has clues. There are absolutely other ways to “safely” discover them aside from breathing.

Because in my experience meta gaming like that is not an issue at 90% of all tables. And at the other 10% it’s just that one guy that causes an issue about trying to meta game their character out of consequences.

RPG Rules are not laws, so they are not written for the lowest common denominator, but for a group of well meaning, socially functioning, above room temperature IQ human persons with a base level of trust.

Not every table preference has to be mentioned in the rules to be legitimate. At my table, there are no secret rolls or checks that a PC makes without a reasonably clear concept of what the consequences of success and failure are. So a list of default stats that your GM can check would be a waste of time and book keeping. If your GM likes to use mystical rolls with undefined consequences and the percussion of hidden dice to increase tension, more power to them. But to me that seems a waste of everybodies time.

What about the kind of evidence that leaves marks on the floor around where the mimic has been moving? Seems to me that’s fair game

Of course it doesn’t guarantee it. That’s why you roll dice.

Does evolution apply to aberations? And would evolution not grant the same benefit to every living being as well? Not to mention, co-evolution would lead to better mimic detection, surely.

I don’t see why I have to deal with your fiction over mine.

In Dark Souls, mimics breathe slowly. Like, 17 seconds per breath. It’s tough to spot, but you can spot it if you’re cautious. Since it’s proven to catch people off guard, but CAN be spotted, I figure, why not use what works?