D&D General Is this a fair trap?

[pemerton]

Its not clear if the Yellow-Mold laden stone can be investigated without disturbing/displacing it. If this is low level and the only way to discover the Yellow Mold is by displacing the ceiling stone, then that is a garbage trap. If not, then its completely legit.

I don't know what level Roger Musson had in mind for this. The components are all in Moldvay Basic and so a GM could set it up for low-level PCs. But Musson published it before Moldvay Basic came out. He would have been thinking of OD&D, I suspect (I think he was a bit of an AD&D sceptic).

It sounds like the architecture of the ceiling is such that you should be able to investigate it without it being disturbed. Otherwise, the mold dispersal would have issues getting to the PCs due to obstruction (even measured in microns, a mold spore is large enough to get obstructed).

If the GM is doing a sufficient job depicting the room's initial conditions, answering the player's questions, honoring their Exploration Turn action resolution, AND the block can be inspected without being interacted with...then its legit. I mean, this room's general layout screams Gelatinous Cube and Yellow Mold is a common trap/foil in B/X. Spidey sense of B/X players of any kind of experience will be tingling big time.

I'm assuming this is low level, but if its 7+ Expert, then you have the Thief climb the wall/ceiling > investigate > discover the mechanism and Yellow Mold. Levitate the Dwarf (that has the Ring of Protection!) > everyone out of the room > Dwarf kills the Yellow Mold with fire > passes the ST with its beefy Death Save! Dwarf somehow fails Death Save you Neutralize Poison (I treated YM as Poison).

Or, you have the Wizard summon a Fire Elemental after its discovered and the FE kills it while everyone leaves the room!

If its low level, the Thief climbs and discovers it while everyone gets the hell out of the room (the lot in life of a Thief). If this is the only way forward, you Levitate the Dwarf and have them kill the Yellow Mold with Fire while everyone leaves the room! After you deal with the mold, throw 5 * Flaming Oil in the pit > sac a length of cloth/rope from the door to the pit > light it > GTFO and let it do its work!

You've seen me post before that I'm not really into skilled play. This is why: what initially promises to be this awesome moment of block-squished Cube and fire and yellow mould everywhere playing havoc, turns into a tedious process of levitating dwarves and everyone leaving the room and making play as procedural and (hence) uninteresting as possible!

(In other words: there's a reason I admire Moldvay Basic only from a distance.)

 

[Manbearcat]

You've seen me post before that I'm not really into skilled play. This is why: what initially promises to be this awesome moment of block-squished Cube and fire and yellow mould everywhere playing havoc, turns into a tedious process of levitating dwarves and everyone leaving the room and making play as procedural and (hence) uninteresting as possible!

(In other words: there's a reason I admire Moldvay Basic only from a distance.)

Are you trying to Jedi Mind Trick hand-wave me with "...this isn't the romantic high fantasy you're looking for..."?

What is more romantic than levitating Dwarves as basically hazardous waste technicians!?

 

[pemerton]

Are you trying to Jedi Mind Trick hand-wave me with "...this isn't the romantic high fantasy you're looking for..."?

What is more romantic than levitating Dwarves as basically hazardous waste technicians!?

It's not a Jedi mind trick; just an old-fashioned statement of preference and ability (it's not a coincidence that the skilled play I don't particularly enjoy is also something I'm not particularly good at!).

EDIT: But I can enjoy it as an outside observer. Hence, for instance, this thread!

 

[Manbearcat]

It's not a Jedi mind trick; just an old-fashioned statement of preference and ability (it's not a coincidence that the skilled play I don't particularly enjoy is also something I'm not particularly good at!).

EDIT: But I can enjoy it as an outside observer. Hence, for instance, this thread!

Still, I would like to see the modern instantiation of this where the foreword isn't written but performed by Movie Guy voice. I wonder what the market share would be:

"IN A WORLD...

WHERE YOU CAN BE A DWARF...

FAKE PIRATE SCOTTSMAN ALE SWILLING STEREOTYPE BY DAY..

LEVITATING HAZARDOUS WASTE DISPOSAL TECHNICIAN BY NIGHT!"

I'm imagining a buy-in creating a D&D even bigger than its hay-day.

 

[Charlaquin]

Do you enough about the mechanical properties of gelatin to help with my post 125 upthread?

I do not, sorry

 

[Maxperson]

You've calculated the static pressure: weight = 170 lb X 1,000 cu feet = 170,000 lb; pressure in psi = 170,000/ 14,400 [the surface area, in sq inches, of the block] = approx 12 psi as you say.

In this trap, though, it is the impulse pressure that seems relevant (qv: I might be able to balance a rock or brick on my head without being squashed; but drop that rock or brick on my head from a balcony and it might kill me!).

Impulse = change in velocity * mass / time of deceleration. Upthread we've established that the velocity of the block at impact is around 8 metres per second. The impact brings it to a stop. The mass in kg is around 77,000 kg. Let's say the deceleration happens over one tenth of a second (in "reality" it probably wouldn't be uniform; I've chosen this figure by Googling some collision web pages and using a generously long figure compared to actual collisions). Then we get impulse = 8 * 77,000 / 0.1 = 6,160,000 N. With a surface area of around 9 sq metres, we get a pressure of around 684,000 Pa. That's about 100 psi.

The more rapid the deceleration the greater the pressure. I don't know what sort of pressure is going to be necessary to splat a Cube. The spongier the Cube and the more deformation it can handle, I guess the greater the deceleration time and thus the less the pressure the Cube suffers. My attempt to Google up the physical properties of jellies wasn't very successful (the webpages and papers that came up weren't ones I could interpret for the purposes of this discussion); so I don't know what a "realistic" set of figures is for a Gelatinous Cube.

I'm considering a few changes for the trap in my game. First, I think I'll make the pit 20' deep and have the cube in the bottom 10'. That will make it even harder to attack from the edge of the pit and allow the stone a greater distance to fall and pick up speed before SPLAT. The second change will be three angled holes on each side of pit. Those holes are tubes down to the bottom of the pit and they will act as pressure hoses to funnel the ooze up and out at an angle, defeating the argument that it won't spray the party.

 

[Maxperson]

Do you enough about the mechanical properties of gelatin to help with my post 125 upthread?

Waaaatch it wiggle! Seeee it jiggle!

 

[pemerton]

I'm considering a few changes for the trap in my game. First, I think I'll make the pit 20' deep and have the cube in the bottom 10'. That will make it even harder to attack from the edge of the pit and allow the stone a greater distance to fall and pick up speed before SPLAT. The second change will be three angled holes on each side of pit. Those holes are tubes down to the bottom of the pit and they will act as pressure hoses to funnel the ooze up and out at an angle, defeating the argument that it won't spray the party.

Those are good changes, I think. I like your high-pressure hoses of Cube!

 

[Charlaquin]

My attempt to Google up the physical properties of jellies wasn't very successful (the webpages and papers that came up weren't ones I could interpret for the purposes of this discussion); so I don't know what a "realistic" set of figures is for a Gelatinous Cube.

One thing I did turn up was this:

“The rigidity or resistance of [a] gel to mechanical deformation is an important physical property and is measured according to arbitrary but standardized conditions. This property is commonly called gel strength, jelly strength, or Bloom value and is often used as an overall measure of physical quality.”

Maybe those terms will help narrow your search.

 

[pemerton]

One thing I did turn up was this:
“The rigidity or resistance of [a] gel to mechanical deformation is an important physical property and is measured according to arbitrary but standardized conditions. This property is commonly called gel strength, jelly strength, or Bloom value and is often used as an overall measure of physical quality.”

Maybe those terms will help narrow your search.

I found some of that stuff too. But having had some friends who did doctoral work on rheology and non-Newtonian fluids (both where chemical engineers) I am confident that the maths will be beyond my ability to interpret or apply! (A warning sign for me: as soon as the paper/web page starts talking about shear forces I know I'm not going to be able to follow it!)