Lost Lab of Kwalish

Omiy checks the double doors for any signs of traps, and listening beyond them for any noises. If it comes back clear, she asks Leann to open the door.

Perception: 11

Investigation: 9 

Leann waits for the door to be checked then will open it.

Omiy checks the door, no signs if traps or triggers anywhere around the door. She listens at the door - silence, but with her ear pressed to the door, she notices it feels surprisingly warm.

"Stand back." Leann says once the warmth of the door is relayed to her. She opens it once everyone has moved back a bit.

A massive ball of molten magma dominates
the entirety of this room. As soon as the
doors open, it begins to flow outwards.

Trap: Fiery Death. This room contains a giant mass of
molten magma. As soon as either door is opened, it floods out. On Initiative count 10, the magma flows 20 ft. through the door dealing 65 fire damage to anyone it touches. The magma cools and hardens in 9 hours after being unleashed

(And how do you want to run this trap? Roll initiative, so we know who is going to be burned? Only think Leann should be close enough, as she had everyone else move back. Guess I'll roll her initiative...)

Leann initiative: 13

Leann, feeling the intense heat as she opens the door, slams it closed and heads back towards the others. (Her initiative was 18, so should be able to have closed the door before initiative 10 would have blocked it open...

Initiative 4

”******* run”

Your initiative was 9 (#2622). That's why we rolled them. I agree Leann is the only one who would get it though; she literally opened the door. If the others want to though, they can, on their initiatives act to try to prevent it - an idea I hadn't really considered before now.  So, if they were standing back, that would be 20ft minimum from the door.  Anyone with initiative above 10 (everyone but Sam) could try to save Leann.

Do any of you want to try and save her:  Huarache, Omiy, Shutorn? 

She weighs 175lbs and is carrying 152lbs of gear, so 327 altogether.  (This information is from Leann's character sheet)

Quote from Wile_E_Coyote >>

Your initiative was 9 (#2622). That's why we rolled them. I agree Leann is the only one who would get it though; she literally opened the door. If the others want to though, they can, on their initiatives act to try to prevent it - an idea I hadn't really considered before now.  So, if they were standing back, that would be 20ft minimum from the door.  Anyone with initiative above 10 (everyone but Sam) could try to save Leann.

Do any of you want to try and save her:  Huarache, Omiy, Shutorn? 

She weighs 175lbs and is carrying 152lbs of gear, so 327 altogether.  (This information is from Leann's character sheet)

 Are now that makes more sense 

“Fire bad”

So, Prestidigitation can "chill... up to 1 cubic foot of nonliving material for 1 hour." How much energy does a single casting of Prestidigitation remove from a cubic foot of nonliving material?

I've done some math here: Lava is ~1000 degrees Celsius (give or take 250 degrees), but we'll say that it can be safely touched at 50 degrees Celsius, so we'll assume it's at 1050 deg C so that 1000 degrees worth of heat needs to be removed. The specific heat of lava is around 0.84 kJ per kg*C, so it takes 840 Joules of energy to heat or cool one kilogram of lava by one degree Celsius. Lava is about 3100 kg/m^3, or about 87.782 kg/ft^3, so I can affect 87.782 kg of lava per six seconds. If you give me an idea of what Prestidigitation can do with water (by your definition), I can take this even further and conclude whether Prestidigitation is an absolutely terrible solution or only a pretty terrible solution.

(Yes, there's a reason why I'm playing an Artificer. I just don't have Absorb Elements prepared and am looking for something more interesting than running away.)

 I do like the math and creative play, so that's is definitely worth an inspiration die. That said, prestidigitation cannot duplicate the effect of another spell, which means it cannot freeze water as can shape water.  That limits it to maximum cooling potential for water (l) of 100°C at STP, a little over 11,600kJ.  If I have my math right that's over 1900kW to do so in 6 seconds.  

I don't think I'm going to be convinced that this cabriolet does this problem, at lay not by just pointing at a large of magma and cooling a ft³ of it.  But that didn't rule out other cantrips.

Math time. He can cool a cubic foot of lava by less than 158.401 degrees Celsius, which is impressive as a "somewhere less than this" limit, but not enough to freeze lava. I guess Huarache will use his turn to run away in the most boring way possible. (I am being sarcastic; he's just running away ordinarily.) His movement speed is 60 ft per round with a dash, but he'll use Feline Agility to make that 120 for the first turn.

Quote from Shonisaurus >>

Math time. He can cool a cubic foot of lava by less than 158.401 degrees Celsius, which is impressive as a "somewhere less than this" limit, but not enough to freeze lava. I guess Huarache will use his turn to run away in the most boring way possible. (I am being sarcastic; he's just running away ordinarily.) His movement speed is 60 ft per round with a dash, but he'll use Feline Agility to make that 120 for the first turn.

 Why don't you just go grab Leann and then run away? Even if it's half speed while doing so, Huarache could easily move the extra 20ft, right?

Omiy’s grabbing Leann and running away. Better still, if you agree that echo can grapple, she’s having her echo to grab Leann (though that doesn’t seem very realistic). So yeah, Omiy’s grabbing Leann and running away. 

(Why doesn't someone, with an initiative over 10, simply shut the door? Closing the door will keep the lava from coming out to start, as the door was keeping it back before now, and it doesn't move until initiative 10, so I assume, if the door is closed prior to initiative 10, the lava will stay stuck behind the door. This assumes there is no trigger that locks the door open or something.)

If Huarache is able to grab Leann, he will do so. If the door looks like it can be shut in time by someone with a -1 to STR (but also with Flash of Genius), then he will try to close it first.

I didn't notice Huara he's strength was below 10.  He's actually too weak to even drag Leann.  You could try to close the door, but your pushing against the weight of a liquid rock flow, so that's going to be pretty rough.  Also, unless you grapple Leann, moving then at half speed, you are carrying her ad an object interaction, so it's that or try the door, though a second person could try the door.  

Omiy's speed is 30, so she can use 20 to get to Leann, then she picks her up, her speed drops by 20, meaning she's out of movement.  If the echo is already manifested, while it cannot interact with Leann to move her, you could use it as a teleport anchor, so you can reach Leann in 15ft of movement instead of 20, but then you still only have 15 and even if you could dash, your movement with -20 from encumbrance is a negative number.   

If I miss something or get any rules just flat wrong, let me know.  I am definitely willing to reassess the above statements.

So, I looked this up...

Q: is pushing/dragging a grappled creature subject to the carrying capacity rules?
A: The rule on moving a grappled creature (PH, 195) works regardless of a creature's weight. It cares about creature size.

You can move a grappled creature regardless of their weight (though it does seem like an unrealistic rule), assuming Leann is willing and no contested rolls are required, even Huarache can drag Leann away. So I would say Huarache will grab Leann and Omiy will try and close the door.

I've read Crawfords post, but the tough ruling is whether or not this is a grapple.  As you note, it is pretty weird to have a creature struggle to carry or even drag the weight of something so massive, but not slow down any when the heavy thing is struggling ro break free.  On the one hand this isn't combat, on the other, we did roll initiative. 

I'm concerned that we'll end up with a silent filibuster situation, where any time there's a trap we just have it effect nobody without letting anything play out.  I really have thought about this a lot since yesterday and I think I'm okay with it, but it's a slide.  I don't want it to kill anybody so it won't, but the hotly contested uncontested grapple exploit , which I describe as such because I think it deliberately opposes the RAI, is not hereby decided.  To me, if a character can do something because they are uniquely suited to it or because it's a creative thing the character does, that has a great chance of succeeding, but this is more like the player metagaming an explanation creatively for why a physically weak character can move something heavier than the rules generally allow, because a rule meant for a different thing but worded vaguely says to ignore weight.

TL/DR: Huarache can move Leann.  I will just tell you that it's not possible to manually close the door rather than let her try and get stuck in the lava flow.  The doors have to swing out and there's a 200ft² blob of magma pushing against it, a thing that happens because the hot air escaping into the hallway reduces the head pressure of the room and basically sucks it out.  A spell might make it possible, but I don't see how.  It will just cool by itself in a few hours and only moves 20ft into the hallway. So, now that we've nerfed the first thing in the place, what do we want to do now?