Rawley lights a torch and throws it forward, then draws his longsword and follows.

"We cannot reach the stairs. We are trapped in this room. You must free us," responds the first voice, rather frail. 

Mermi chimes in. "Yes, hungry. Five days now."

Mola takes a few steps westward, toward the sound of the voices, before Rawley sends a torch down the hallway. It skitters across the floor and emits a shower of sparks before coming to a stop. The light reveals that the hallway does indeed open to the left and right. How large the space might be, however, is impossible to tell from the party's perspective. The far reaches of the torchlight reveal a heavy layer of debris upon the floor. The back and forth dance between light and shadow make it very hard to determine the exact nature of the debris. Is it rubble? Wood? Bones? Trash?

Rawley goes forward 30-40 feet, then lights and throws another torch in the same direction. "Whoever it knows we are here. Lets shed some light on this situation."

Rixton creeps forward all the way to the first torch, not worrying about being noisy or seen, but simply on guard for any sudden attack.

(Move, dash, dodge.)

Mola's not sure Mermi's really all above board, especially given that last bit. Can he tell from where the voices are coming, within the next room?

He steps forward about 10 feet, and casts faerie fire on a point 60 feet away, in the visual range of the large room. The 20-ft radius cube looks like it would affect most things in this part of the chamber, as well as perhaps quite a bit into the darker parts. The idea being to reveal any hidden beings/objects/effects in the chamber, as well as Mermi and his friend, assuming the voices seem to be coming from this general area.

He'll also cast produce flame and look for places to start to throw it, to reveal more of the chamber beyond the torchlight, and looking to avoid igniting any debris that seems worth investigating or gathering. 

Gwin, with crossbow at the ready, edges to the front of the group using her darkvision to see if she can make any figures out. If she can get close enough to the first torch, she will cast Thaumaturgy, causing the torch flame to brighten even more (hopefully).

(NOTE: Faerie fire only covers an area of 20' x 20' x 20'; so, it won't really add much to the two torches)

The two torches--one of which now burns more brightly as a result of Gwin's incantation--illuminate a substantial area in front of the four adventurers. From his vantage point, Rixton can see the large open area that extends to the left and right of the hallway. The debris on the floor is comprised wholly of bones--bleached white bones, some of which have turned to powder. Rixton estimates the skeletal remains (none of which are in tact) represent hundreds of dead creatures. At the far end of each room (to the north and to the south) are two alcoves. In one alcove stands a semi-circular stone enclosure of some sort. In the other alcove is an almost-square enclosure made of wood. The walls of both enclosure are roughly three-and-half feet high. 

"Wonderful. They're coming our way, Mermi."

The voices seem to come from beyond the large open room, somewhere farther to the west, somewhere beyond the reach of the torchlight...

Oh Mola wasn't trying to use the spell to illuminate, he was trying to reveal anything invisible, or target the voices. They're pretty far, though, so if there's nothing invisible, this seems fairly useless, and not only because I'm an idiot and wrote "20 ft radius cube" which is not geometrically a thing, and also much smaller than I thought!

He says, quietly, "I don't think they're victims here. Smells like a trap to me. Want me to go spring it? Large snakes or a dinosaur or something else mean and nasty?"

If the party assents, he'll walk in, expecting a trap before he'd get close to where the voices are.

Rixton motions Mola to halt.

"Mermi, would you like to play a game while we look for you?" he says. "It s called 20 questions. Have you ever played it before?"

While Rixton talks, he will move forward veeery slowly to the next torch.

Rawley walks up to the extra bright torch and once again chucks it forward towards the voices.

Gwin says, I've got a baaaaaaad feeling about this as she continues to cast Thaumaturgy on each torch she nears.

Mola's remark about how things smell suddenly takes on an unexpected meaning as the four adventurers continue their slow advance down the hall. A foul, rotting odor reaches everyone's nostrils as they reach the first torch. The second torch, after being thrown again by Rawley, reveals a gentle right turn in the main passageway The sound of the two voices is coming from just around the bend.

As the thrown torch skitters to a stop, the first phantom voice responds, "Ah! So bright. Yes. Yes. This way. Just a bit farther now."

Mermi responds to Rixton. "Questions? A game? No that won't do at all. We are trapped. Free us, then we will play games."

As soon as Mermi finishes speaking, all four adventurers hear a faint noise to their left. Quickly turning their heads to the south, they see a ghastly humanoid stepping out of the semi-circular enclosure. It almost seems cloaked in shadow, and its tongue and claws are something found only in nightmares...

...and it quickly closes the gap on Gwin, first slashing at her with its long, needle-like claws, then opening its gaping mouth and trying to bite her...

 ...but the dwarf is more than ready for the attacks. She evades both, but now understands the source of the foul odor. The creature's stench is overwhelming...

...but she fights through its nauseating effects. 

All creatures may act, in any order. 

(What happened to the creature?)

I forgot to add it to the map. Map has been corrected now.

Bonus action: Mola morphs into a giant constrictor snake and slithers forward and around the monstrosity, flanking it with Gwin.

As Molasnake brushes close to it, his tail lashes out, attempting to constrict the gross thing for its action.

Attack: 17 Damage: 11

If it lands, the target is grappled, with an escape DC of 16.

Rixton is right behind Molasnake, slashing at the ghastly thing with his shortsword, followed by a kick and a palm strike to the thing's face.

As he imparts his violence, Rixton casually continues his conversation with Mermi, ignoring the voice's rejection. "Ugh. Well, I have my thing in mind, Mermi! Let's make it a little more interesting, though. If you have not guessed what I am thinking after 20 questions, I get to ask a favor of you. If you do guess it correctly before then, you get to ask any favor of me. I'll even give you a head start. I'm thinking of a place. Just ask me yes or no questions and I will tell you truthfully the answer about the place I am thinking of. Let's see if you can figure out my place before we make it to you."

Rawley takes up yet another side around the creature and tries to skewer it twice with his longsword (also with advantage as we surrounded it? ):

Attack: 28 Damage: 12

Attack: 27 Damage: 12

The shadowy creature is quickly overwhelmed by the three-fold attack of Molasnake, Rixton, and Rawley. After being grappled by Molasnake, the creature is nearly helpless against the the melee attacks of Rixton and Rawley, whose first slash with the longsword nearly cleaves the ghast in two. Its vile stench is the only defense the creature has before it dies...

 ...Molasnake and Rawley retch slightly in response to the creature's odor, but Rixton becomes quite ill, feeling physically weak and mentally confused. Gwin looks upon the slain ghast and can only wonder what action she might have taken against it had her companions not dispatched it so quickly. 

The adventurers have only a few seconds to ponder the horror that they have just defeated before the sounds of more activity reach their ears. The voices from the darkness suddenly reveal themselves by rushing down the hallway (and none of them seem interested in continuing a conversation with Rixton) while another shadowy ghast-like creature clambers out of the enclosure to the north. The three humanoids to the west are very similar but not identical to the shadowy ghast-like creatures in the main room. 

All players may act, in any order. Rixton is poisoned for one turn. 

Rawley moves 30 feet directly west to stop at the corner and takes the Dodge action.

"Keep talking ********, one down, four to go."

Rixton's stomach lurches as the room spins around him. He sheaths his shortsword by muscle memory alone and unstraps his throwing ax as he focuses on the ghast across the room to his north. Still, he somehow finds a way to quip. "Mermi, it is so good to see you. You lost the game, though, so you owe me a favor."

Rixton studies the ghast to the north, ignoring Mermi and the others approaching from the west. His vision swims as he tries to identify the weaknesses of the ghast.

Insightful fighting: 11 (vs. deception of the ghast)

Then, the rogue taps the amulet hanging from his neck. The world suddenly makes sense again and Rixton can see how is throwing arm connects all the way across the room to the ghast. The head of the ghast looks like a tempting target in this momentary state. Rixton releases his throwing ax.

Throwing ax Attack (with clockwork amulet assist): 18 Damage: 9 + 11 on a successful insight check