[It was just the wife and I in my truck, other than hurting like no tomorrow we are OK, nothing broken, and no surgeries as of right now. Had the kids been in the car they would have been a different story.)

As the next on slaught of attacks come at the fish it losses life and dies.

Mist make a nature or religion check for me.

Jecob on your second attempt to pull the sword free you manage to do so. 

Also the ice wall now falls. 

Jecob you were in the room when it fell you will take 3 fire damage at the start of your turn along with anyone else who enters the chamber, unless something is done like before.

Nature/religion (same bonus): 4 (lol)

Seeing the ice melt and Jecob get burned, Mist will assist with further castings of shape water if needed to get him the rest of the way out safely (as well as if we need to get through to the other side of the room to progress).

Mist you have no clue about the fish other than it does not look normal.

Mist make a spell attack for me, at advantage pleae.

Spell attack (rolled as an eldritch blast in the campaign roller): 27

Jecob tumbles out of the room, as he started moving for the chamber exit as soon as he freed the sword. He still gets swamped by overheated water before he could reach the outside corridor, but he only receives a few minor burns (1 damage).

"Thanks for getting that fish off my back.
Unless there is something else to see in that room, maybe we should move further away from those heat vents before one of you arcane types examines the sword."

The Ice walls are up and doing their jobs.  Everyone is able to cross with no problems.  We now are at a t intercetion.  

The head informs you "To the north is the grato, and to the south is Ihu’qancao’s favorite pet"

"Grotto. Grotto?" Mist nods curtly to the others. Back to the head, he says, "Grotto."

Kraven lifts the head up and asks it, "What might be in the grotto and did you say pet? What could possibly be a god/demon's pet?"

Mist chortles. "What COULDN'T be a god/demon's pet??"

"I just know I'd rather avoid anything associated with Mxyzptlk if given the choice."

“Yes, the grotto seems the better choice, for sure.”  Kuatho says, ready to keep exploring.

Jecob taps Mist on the shoulder with the pommel of the recovered sword.
He'd like to hand it off to someone who could use it, or is skilled in seeing if this is a non-standard sword.

(Or maybe had writings on the blade saying which way the group should go?)

With out Identify spell it will take a short rest to identify.

The Grotto is Ihu’qancao "lair" if you would.  Most likly place the Star would have been taken to.

"Eh?" Mist grunts. "Thanks, but I've got no use for that, now do I? Thing's almost as big as I am! You hang on to it and we'll see how much gold we can get for it once we get back to civilization."

He looks back to Kraven and nods in the direction of the grotto.

Nodding his head at Mist Kraven swims across the walled off heated water area briefly stopping at the dead fish seeing if it has anything of value on or in it. Then will move north toward the grotto as silently as he can swim hoping to detect anything amiss before it detects him.

Fish Investigation: 15

Perception moving down the hallway: 17

Stealth moving down hallway: 14

Mist follows but a ways back. Not emerging into the grotto until Kraven gives the all clear, but not staying so far behind that he can't help if something happens.

In the center of the grotto rests the long-sought Fallen Star, surrounded by demonic runes of power.

The Fallen Star is striking. The size of a large melon, it is far larger than the shards the party has encountered so far. It appears to be made of a single lump of metal, like a cooled ball of molten gleaming adamantine. Strong silvery light - a shocking contrast to the oppressive darkness of the demon grotto - shines forth from it; a quality of light that is exactly like brilliant starlight on a clear night.

The Fallen Star is surrounded by three Abyssal runes of power. A merfolk attends one of the runes each. The three merfolk mutter incantations in unison over the runes and appear to be siphoning power from the Fallen Star.  A figure (assumeably Ihu’qancao) circles at the far end of the room, opposite the entrance to the chamber.

A chasm stands agape with an other figure impatiently attempting to squeeze through. All along the bottom of the chasm, a glistening black and red portal shudders and stretches. Feathers and mouths lined with sharp teeth piece through the portal momentarily before they’re pushed back into hell.

Ihu’qancao thunders "Finish with the last part of this ritual immediately, or else!  Father fear not soon this shale be done and this world will be yours!"

On the other side of the fracturing seal, an enormous black and gold eye, adorned with matted green feathers along its edges, stares into the room. An ear-splitting roar thunders through the chamber as Ihu'qancao's father attempts to push his way through the small crack. The water around you trembles violently and bits of rock are shaken loose from the ceiling.

Can I get from everyone either a religion or an insight check please.

Also Roll20 has been updated please adjust your pieces as we come into the game.

Insight : 21

Kraven will look back down the passageway when he hears anyone approaching and moves his feathered hand to signal them to approach slowly and as quietly as they can.

Kraven you can tell that these merfolk are not doing their own bidding, their eyes are glassed over.

As you are signialing for everyone else to come down you hear "Yes bring your friends down they can be my meal to share with father!"

Jecob Insight check (from game log): 13

He notices a lot less than Kraven, due to this strange sight.