Road to Phandalin

Map:

Possible routes in no particular order:

• leave the cave
• get somehow past the slime
• go through the mushroom cave
• there was a door leading west at the furnace
• there was a tunnel leading east at the furnace
• there was the dryed up water supply near the furnace

"Let's head back to the furnace and see about those doors there..." Dain suggests.

"Gods, that thing was right down the corridor! What was that Dain? You seemed to know what it was how did you handle it?" 

She looks frustrated 

"A far better plan. Wouldn't want to get trapped going down the wrong corridor with that." Nobody chimed in, appearing to understand or at least have a rough idea regarding the nature of the danger. He also dismisses and summons Karasym back to his side, only to have him fly ahead as the group made for the furnace. Just in case any other creepy crawlers decided to relocate to the area in the time they were gone.

Along the way he thought about the strange thing in the hall, halfway wondering if it could be used somehow later..

Arcana: 20.

But like the Bugbear, which despite passing near, he was not keen on getting closer to if it meant suffering an ill fate, anything that came to mind was set aside for future nobody to exploit later, if at all.

When back the furnace room again, he suggests trying the tunnel leading east, since it hopefully by then bypassed any fungal sections well enough. But he just as fine checking out the door as well.

Based on the size and the transparency you assume it is a Gelatinous Cube.

(with that 20, feel free to use all the info from the linked monster)

"I'd rather not deal with the goo." Dain says with a glance in that direction. "We have other ways to look first, and the furnace room in particular might lead to places we actually wish to go..."

Otrov

”Goo?  What kind of goo?  Good goo?  Is there good goo, I wonder?  Are you all talking to each other invisibly?  Hmmph.”  Otrov acts put off but perks up at the mention of the furnace and possibly making something statuesque. 

Margret says to Otrov "The kind of goo that would eat you alive Otrov. At least what I can gather, Dains familiar saw it first and warned us thank the gods. I think we wouldn't have our spirits with us now"

We have not moved yet I guess

"There is a big ball of goo down that way." Dain says, nodding in the direction of the thing. "It is pretty much a huge ball of acid, that I would rather not have to deal with, since we don't have any reason to go in that direction as of yet." He glances to the others. "Are we agreed to head back to the furnace again then?" He summons Sabastian back to his side, then has the familiar check out the mushroom area, while they decide things.

Otrov

”oh THAT Kind of goo. Me and Dain killed one of them before.” She hops away, unafraid, and looks around at the local flora seeing if anything might be useful. 

You carefully move back to the banquette hall, where you come across a small swarm of stirges, but you take quickly care of them, before you move on to the furnace.

Otrov 

Otrov has her lantern lit (unless there is another light source from Margret) and creeps along ahead, listening for shambling undead or the tell-tale rattle of bones to indicate animating skeletons.  As long as all is okay, she will proceed into the furnace room and take a closer look at the room, the furnace, the bodies...And to think, I could have been one of these ghoulish things, forced to animate and attack, she shivers at the thought.

Rolls if needed

Beside the stirges and the occasionally crushing weave echo, everything is quiet.

On the way there after tangling with the striges Margret takes her dagger and drills a small  hole  in the top of the skull refreshed green lighted 

"Hey Otrov got any string?"

Otrov...

...hands her some rope. 

The door is just west of the furnace, it is closed at the moment.

Wishing that Nobody would at least try what she suggested she ties the twine  to the hole and hands the rope to Marco and gets him to fly in circles above but aways away from them

Marco Stealth 9

Seeing others side-tracked again by skulls and crafts, Nobody just shook his head, and opts to head over to the door at the western half of the furnace for a listen at it.

Perception: 2.

If he can hear nothing coming from the other side, he would then take a closer look at the door itself to see if there's even the slightest gap that Karasym might be able so squeeze through quietly before the tiefling backs away and switches to the flying snake's sensors.

You can not hear anything and  doors here were build by dwarfs and gnomes, they seam to fit perfectly.

Being happy with her goulish arts and crafts she checks out the west door herself Perception 12

Listening and for traps and if its locked