Keyleth gives Wulgar a skeptical look. "Really? You think they want us to piss? Between that and blood, I'm guessing it's blood. It tends to be that."

She does join him in investigating the room, though.

Investigation: 26

     “Long time no see,” Mulligan says as lightheartedly as possible through the poisonous air.  He then sets about taking a quick glance around (mainly just to see if there is a drift globe here.)  If there is a drift globe he’ll try grabbing it on the off chance it sends him right back out…  if no globe he starts investigating the rubble where jewels were found in last room.

     “Boy did you bring us to the wrong place, lucky I’m here to help save ya,” he manages to say to Avarice.

investigation: 21
2nd Con Check: 4

*cough* I’ve got a bad feeling about this…

Avarice looks up at Mulligan, a bit surprised as he didn´t expect him to be the first to come along. "I´m not sure I brought anyone of us here, but I´m looking forward to seeing you saving us from this death trap." He says with a wry smile while looking around the room for clues.
Perception with help from Vorax, who is quite untroubled by the toxic environment:26
New con save: 22

Does the poisonous gas cover the whole room? Is the poisonous gas magical in nature? Could we safely retreat into Avarice´s portable hole for a few minutes?

Wulgar is down on the floor, looking at the spiral that he thinks he sees, checking for any grooves, or any spot that liquids would go.  "There's also sweat, tears, spit and crap.  I'm not going to start crapping in her to get out.   I can't sweat.  I don't feel like crying.  I can bring up a nice wad of spit, but there may be a little flame that comes out with it."  He keeps examining the floor, the walls as he's talking.   

Investigation :  6 

As Ragnar presses his palm into his blade, a few drops of blood spill to the ground - to be immediately greeted with the sound of hissing almost pleasant as the runes etched into the ground glow wherever blood was spilt. 

Wulgar and Keyleth, indeed - on the ground is a roughly spiral-shaped series of indentations carved to look like glyphs. You assume that quite a lot of blood indeed must be spilt on the ground for the runes to be, well, satisfied. With Keyleth’s score, you assume it takes, for lack of better terms, blood loss of roughly 50 points to complete. 

Varan isn’t quite as well-versed in the arts of the arcane as others; the only thing he can ascertain is the magic altering time around him is ancient and powerful in nature. 

Mulligan and Avarice, however, wrangle the poisonous room - taking 6 Poison damage on a failed save, or half as much on a successful one (DC15). There is no driftglobe. The fog definitely envelops the entire room, limiting sight to barely an arm’s length in front of you. Mulligan sifts through the rocks with surprising speed and accuracy - though unlike the last room, nothing of interest lies inside. 

Avarice attempts to scan the room for anything worth noting - and with a 25, even with the fog’s limits, he manages to spot a series of ridges lining the stone pillars of the room which weren’t in the first room you found. 

Make another two con saves! 

"Over here." Avarice says to Mulligan, trying to keep his calm within the poisonous cloud, moving closer to the ridges together with Vorax to take a closer look.
Investigation of ridges trying to determine their purpose, with help from Vorax:11 New con save:8

Is the poisonous gas magical in nature? Could we safely retreat into Avarice´s portable hole for a few minutes?

Keyleth looks at Wulgar. "Yeah, it's blood. And it looks like we'll need to spill a sizable amount."

No sense waiting then... and no time like the present.  Varan will replace the ruby with the emerald, turning the driftglobe green and then he will reach out and touch it.  

Another two con saves each?

18 and 20

     Mulligan, finding nothing, will respond to Avarice’s call and check out the ridges he indicates.  “Interesting,” he’ll say but truthfully will be finding the poison more interesting.  He’ll use his arcana sills 8 to try to determine if the poison is indeed magical in nature, thinking perhaps a Dispel Magic may help if so…

Ragnar frowns.

”Then so be it. I doubt our captor will value the blood of a king more, so let us all share equally in the spilling.”

He readies Frost brand and looks to the others, ready to cut a small gash in his bicep.

(Ragnar can take 20 hp, and Keyleth and Wuldgar can take 15)

Keyleth thinks to herself that the other two can probably take a lot more in the way of hits than she can. She then dismisses this thought, because it doesn’t make any difference.

”Sounds good.” She readies one of her shortswords for a new target—herself.

(I meant one con save for each of you, apologies for being unclear.)

The poisonous fog is, made abundantly evident by its magical properties, magical in nature. It seems to flood through the entirety of the chamber - no corner is left unobscured by the oppressive mist. A normal substance so heavy would likely pool at the ground, but it seems to reach all the way to the ceiling. You may certainly try to enter the portable hole. 

Avarice lays his hands over the columns and attempts to discern what the patterned etchings mean - the best he can come up with is the pattern of ridges, bumps, and sockets mean to spell some sort of message, though he isn't quite able to tell what. 

Avarice and Mulligan take 9 poison damage, half on a successful DC 15 Con save (Mulligan, use the first you rolled). 

Meanwhile, a flash lights up in the fog as Varan jaunts inside. Con save from all three! 

     Annoyed and bothered by the poisonous fog, Mulligan still feels it could be much worse.  Yay for clean living, he thinks. Relative to the company I'm with, anyway...

     Still, life would b e better, and probably longer, without the poison...  So Mulligan attempts to Clear the Air ... (3rd level Dispel Magic, lvl 3 or below is dispelled, ability check of 8 if spell is 4th or higher, the DC is 10+spell level...)

     If the poison spell not level 3 or lower, Mulligan hacks and coughs a bit to try and hide the fact he had even tried to Dispel it and failed...  

"Hurry, we need to figure out what these patterns mean, I believe it is our only way to leave this toxic environment." Avarice says desperately to Mulligan and the newly arrived Varan.
Arcana/Investigation with help from Vorax to discern message:16

So since the poisonous gas is a magical effect Vorax would give Avarice advantage on the saves right?
Another con save for last round:23 A new with advantage for this round:19

Wulgar takes out his dagger and pulls up the sleeve on his left forearm.  "If I'm going to do this, let me make something out of it."  He slices a spear shaped cut into his left forearm, enough to allow blood to flow, allowing roughly a half to a full pint of blood (15 hp worth) onto the ground, in the grooves and joining the blood of Keyleth and Ragnar.   "Raarrr.  Yeah!"  The red Dragonborn seems almost excited at the sight of his own blood and appears even more animated, agitated.  

Ragnar traces Frost Brand down an old, silvered scar in his bicep; a scar that old Ayedimir gave him years ago. He grimaces yet doesn't make a sound as the dark blood trickles down his arm into the glyphs. 

(20 hp) 

Keyleth cuts a gash into her forearm, gritting her teeth as she lets the blood drip onto the glyphs.

(15 hp)

CON  24

Varan steps out into the green mists alongside Avarice and Mulligan.  "(cough) Poison.  Green stone.  Of course.  (cough)  Classic, if a bit predictable, " he says to no one in particular.  As he examines the room (Investigation 28 ) he looks at his two fellows.  "How nice to meet you again.  I suspect I shall last a bit longer here than either of you, but its in all our interests to figure out the game here quickly.  Oh... and how long has it been since you two arrived in this room?"

Wulgar looks at Keyleth and nods, then says “Let’s be damned sure it is enough.”  He opens the gash on his forearm a little wider and more blood hits the ground.  (10 more HP worth).

"Less than a minute, but I think the poisonous gas will wear us all down within minutes. Hurry over here Varan, help me decrypt these patterns!" Avarice says to the newly arrived half-elf.