D&D General Is this a fair trap?

[pemerton]

Then there is the matter of the forced-damped harmonic oscilation after collision with the cube.

And what is the viscosity of the cube? It's structural integrity?

I've never dropped a brick on a plate of jelly, but this thread is making me think I should, to do some concept-testing.

This also seems relevant to the issue of weapons vs this Cube. How do weapons hurt a Gelatinous Cube? Just by hacking it into little bits? In which case being in the pit gives it quite a bit of protection!

 

[pemerton]

That's an overestimate so something is wrong with your calculations (a human and a block won't be significantly different here).

Yes they will be. The density of a stone block is a bit different from a human being. And I said I was ignoring air resistance - your chart is for sky divers!

Re yellow mould (from the AD&D MM):

deadly spores shoot out in an asphyxiating cloud, 1" by 1" by 1", originating from the center of impact. Any creature which is within this cloud will die, its lungs filled with yellow mold growth, unless it makes a saving throw versus poison. A cure disease and a resurrection are necessary within 24 hours to save such victims.

Yellow mold is affected only by fire based attacks - flaming oil, a fire elemental, etc.​

So it depends on where the centre of impact is taken to occur.

 

[Ruin Explorer]

I've never dropped a brick on a plate of jelly, but this thread is thinking I should, to do some concept-testing.

This also seems relevant to the issue of weapons vs this Cube. How do weapons hurt a Gelatinous Cube? Just by hacking it into little bits? In which case being in the pit gives it quite a bit of protection!

If you want to simulate the trap as written, the jelly needs to be in a flower-pot or something (with some rim above it), and the brick needs to be a half-brick and dropped from like the height of the flower pot.

If you want to simulate it the modified way I suggested you're probably going to lose some crockery but you can put a big block of jello with a chess-piece in it on a plate, and drop the heaviest small plate you have on it, or just forcibly squish it (you could have it as a mechanical trap), then drop a small weight from like 3x the height of the jello on that.

Yes they will be. The density of a stone block is a bit different from a human being. And I said I was ignoring air resistance - your chart is for sky divers!

I don't think they will be, actually. The terminal velocities will be pretty different, but the initial acceleration will be extremely similar. This is not complex physics. I am very unclear why you think they will accelerate significantly differently. And you leaving out air resistance is your decision mate, but it makes your figure even less accurate.

Re: the cloud, is a 1" cube (i.e the blast area) in 1E terms 10x10x10 or 5x5x5 or some other dimension? Either way it's not getting anyone not actually in the pit with it.

Also I finally got the 1E MM open and you left out how it's 50% chance that an impact, not 100% as the trap implies. And I'm not sure smoothly dropping into goo counts as an "impact". And as it has 0 HP and no HD any fire damage at all does indeed insta-kill it.

 

[Laurefindel]

None of those explanations should IMHO be a concern for the players. If I play the game, I take whatever is coming and try to beat it. Sometimes I fail, and some of my characters even died sometimes, but I keep playing, I don't start contesting the economy behind a trap. If the players feel something is/was too difficult to beat, they're right to bring it up to the DM, who has the responsibility of keeping a reasonable level of challenge (too hard or too easy spoils the fun). But I do not accept players who argue the "logic" of a story element at the table, as if such players would be capable of doing a perfect job... most of the times they are just resenting the fact that they weren't able to to win. Off the table, sure go ahead, we've been here 20+ years already indulging in theorycrafting after all.

Besides... I wish that I would react with a "who though of that!" more often when playing, that would be amazing.

I believe they can be a legitimate concern for players. One of the DM's job is to provide a believable world. Now by nature, fantasy, as a genre, will introduce unbelievable elements, but they should be used coherently.

Even for the characters who are accustomed to flying dragons and receiving fireballs in the face, some things remain suspiciously improbable. This usually indicates that there is more to it and that the puzzle is incomplete. The DM, of all people, should have a good grasp of what the "big picture" is.

 

[iserith]

Yes, it's fair. The players have ample opportunity to explore what's going on in this challenge before purposefully or accidentally setting it off. One would hope there's a way to examine the ceiling to notice the block and that the gelatinous cube can be attacked by some means other than fire from a distance (reach or ranged weapon), but I don't know what rules apply to the cubes of that era. The room isn't presented as something that must be gotten past (e.g. the only way deeper into the dungeon is past the pit), so it could easily be left alone. If it is a room that must be gotten past, then a 10 foot pit isn't all that hard to traverse, depending on the PCs' equipment.

 

[kenada]

Skilled play!

That seems to be the crux of it. If the trap is “realistic”, then it’s unlikely to be evident from the environment. Otherwise, it’s not a very good trap. If the former’s the case, then PCs won’t engage with the environment to find the trap. They’ll tell the GM they’re following whatever standard procedure they’ve devised for finding traps, and the GM will play the game for them (telling them when they find something and ask what they do or to roll a check).

We can argue over whether the trap you described makes any sense or actually works. I’m willing to admit it probably doesn’t work as described, which would render it ineffective at its purpose (or hilarious if portraying the dungeon’s keeper as incompetent is the point). However, I think you need that style of trap. It’s like the traps in the Indiana Jones movies. Who builds an invisible bridge over a bottomless pit? How are those scything blades in such good shape? But it makes for interesting scenes where Indy has to figure them out and overcome them.

As for this particular trap, assuming for argument’s purpose that it can actually function as described, then the issue of its incongruity can be addressed by figuring out how it actually fits into the dungeon’s ecology. Is there a way to bypass it for those who inhabit the dungeon (e.g., using a plank, as was suggested by @clearstream). Is there a kobold with a tiny cowboy hat who’s responsible for wrangling new cubes when the old one gets squished? Is there a hoisting team with jacks and protective masks for putting the block back into place? Answering questions like these will help you contextualize the dungeon.

 

[Reynard]

Nothing kills the fun of dungeon exploration more quickly than demands for realism and plausibility.

It is a little piece of Hell that has wormed its way up close enough to the surface to draw in the foolish and unwary. it exists as a malevolence and a hunger. It wants to kill you, but it wants to make you scream first.

 

[Crimson Longinus]

Nothing kills the fun of dungeon exploration more quickly than demands for realism and plausibility.

Then you cannot have skilled play. Anything can be anything, and any action can result any outcome. You need coherence in order to be able to make informed and meaningful decisions.

 

[Umbran]

No, it is a stupidly implausible and convoluted nonsense trap.

painfully stupid nonsense.

Mod Note:
Dude, could you tone the rhetoric down just a tad, please and thanks?

 

[Stormonu]

Seems like a typical old-school trap.

Further discussion
All I can say is that this is one of those traps designed to turn your 10’ pole into a 4’ pole. Easily discerned by a bag of flour or tossing a stone or sack into the pit (or the halfling) when testing to see if it’s a weighted trap.

I think the “you can’t see the cube no matter what” is shakey (if the cube is sitting on treasure, someone might see it shift or begin to float in the cube, at least), otherwise it’s an obvious trap, though the solution might not be so.

Nowadays, I‘d be more concerned why the cube hasn’t starved to death sitting in pit with nothing to consume. Or why it couldn’t “climb” out to chase the party.