Peri:

Peri withdraws to Kei's location just around the corner from the guard post. (Presumably Boktopus comes with him?) He whispers to Boko, asking her to change color to something bright for a moment so that Kei can find them. Once they've all gathered, he puts his head near the others' and quietly brings Kei up to speed. " The gate is closed; no way I can see to wreck it without being noticed. The net is disabled, for what it's worth. We didn't really get much, but I don't know what more we can do here. Head back to the others or try to get past the guards and up to the next level? Seems like we've taken big risks with nothin' to show for it, but I'm stumped for ideas."

Qivys finishes off the last sahuagin. All is quiet.

Gerrard:

”Quickly, let’s get back into the prison and shut the door,” says Gerrard as he drags the last body back inside.  “Any idea what to do with the bodies—maybe stage them as a prison break and jab them with their own weapons? Whatever we do, it needs to be quick and remove all evidence of anything but the prisoners being here before they ‘broke out’,” he adds, “Hopefully they will think the prisoners escaped some other way and not bother to move the eel once we set it back in place and lock the door behind us.”

Qivys shrugs his shoulders as he helps get the bodies inside. He will look the bodies over for anything that might be useful to the party.
Any weapons, keys, trinkets, coin, and the like.

Other than their spears, a few coppers, and some personal items, the slain sahuagin have little in the way of weapons.

The door is shut; Gerrard, Qivys, and the others are back in the torture room with three sahuagin bodies.

Gerrard:

”Borgas, Kysh, I think it is about time for us to leave.  Take what weapons you need from the dead guards and let’s stuff their bodies in a cell or two—maybe propped up where you were sitting in case they don’t look too close.  If we shut the cell doors they may not be noticed for awhile if the fates favor us,” says Gerrard.

He helps to hide the bodies and works to maneuver their freed prisoners past the dead eel body and to the other side of the secret door. “We’ll need to keep a watch for the return of the others,” he adds, “I don’t think we’ll survive another patrol if they come this way, but we can’t leave our friends behind either.”

(Planning to get prepared for a hasty exit if the Sahuagin are on the heels of the stealth party on the way out.)

Boktopus flashes pale white once and then back to camouflage. She taps once on the shoulder (if she can find it) when Peri says head back to the others and then points with a tentacle back down the hallway where they came from.

Kei 

The frustration in Peri's voice is painfully clear. Kei too didn't want to leave without something. Forgoing his usual need for treasure he replies to the invisible halfling. "These filthy creatures don't even have a treasure room. All they want is to watch each other smash heads. I say we leave. We've disabled one of their defences that's enough." He calls Krill to his side before dismissing it back to its small pocket of space. Without waiting for a consensus he turns 180° and blindly takes a step. He stops. "You know I can't see a thing" he gruffs at Peri as if demanding he be escorted.

Peri:

With Boko and Kei both indicating their desire to return (Kei rather more testiliy than necessary, in Peri's opinion) Peri wasn't about to argue. This whole mission had been a boondoggle and he had no desire to die on such an ill-conceived escapade. He leads Kei back as quickly as they can stealthily move through the tunnels.

The three sahuagin bodies are hastily stuffed into a couple of cells, and Kysh lowers the bars on both.

Everyone begins to squeeze past the dead eel; Borgas breaks into tears again as he does so. The massive Sea Lion has a very difficult time squeezing past - it is a lengthy struggle, by which time Peri, Boko, and Kei have returned. With their help, everyone pushes through and reconvenes in the rough-hewn tunnel leading to the abandoned north exit under the causeway.

The hallways remain quiet in the meantime. If the last sahuagin raised an alarm of any kind, they are certainly slow to respond. 

Gerrard:

”Mistress Boko, I think you are going to need to lock the cell door for the giant eel like you opened it to maintain our secrecy,” says Gerrard to his transformed friend.  He turns to Peri and asks, “What else should we do to remove evidence of our visit?”

As they are waiting to leave, Gerrard asks those rescued,, “Master Borgas, Emissary Kysh, what will you do now?”

If Boko can, she stays in octopus form and tries squeezing past the eel back into the prison once the door is closed, and tries to lift the bar up, back so it's locking the cell. She does her best to try to ensure that the place largely looks as it did when they arrived, and leaving no clue how the party got in. She'd like to give the assault the option to go in with surprise if possible.

Once she does that, she returns back underneath the door, past the eel, and into the passageway. She shifts back into herself. 

"Hello. I am Boko Alcor. I am not an octopus, I am a druid. I am sorry you suffered in there. I am glad you are free. I am sorry about the loss of your impressive eel friend. I am sorry we kept you waiting, and hope you were not too bored. Gerrard, Kei, Peri, and Qivys, let me tell you about what I saw on my scouting forays." (She relays all she saw... the other barracks, the possible spellcaster, the stairs up, the seaweed, the armory, the room with more battle armored sharks, the general layout, and as precise of numbers she can guess at.)

"So we could return home with what we now know, and two freed prisoners. Or... we could try going in the front door, so that at the very least those sharks and the more aquatic sahuagin are at a disadvantage, assuming it is not filled with water. It may be more disruptive, and we could easily be seen, but we should learn more, and have an opportunity to soften things up for a real attack. They are still shaping this place from what it was to what they hope it will be, correct? Perhaps it is under construction at the top. That would be good to know. And I for one have not fought these brutes and would not refuse the chance to do so."

Is the size of the building large enough seeming that the top is really far from the bottom? Or is it rather close together, so a skirmish at the top might not be noticed at this bottom level?

The winch is released and the door closes under the pressure of the body of the bloated eel. Boktopus struggles with the heavy bar, but is finally able to re-latch it. Finally, she successfully slips back through to rejoin the party. 

This place is huge, sprawling, and separated by a lot of solid rock. The tunnel in which they now stand is some 80 feet below the surface. The rooms and hallways they've seen were all at least 15-20 feet tall; the ceiling of the arena was about 60 feet high. The stone walls separating the adjacent areas they've seen so far were never less than three feet thick. Sound doesn't seem to travel well through walls or down the twisting corridors.

Peri:

"If we can get that slab in place, the devils won't likely find the exit. Qivys, think you and the sea lion can heave that thing back?" Moving closer to Borgas he speaks quietly. "It's a shame your eel didn't make it, but it was his effort that gave us a way in to free you. And if we're lucky, it'll be that same hole we use to slip a force in to gut 'em from the inside while they're lookin' out."

Qivys nods.
"With tha' right help I think it can be done." he responds to Peri.

Gerrard:

Gerrard will Help as well.

If Boko can shape water to help, she will. 

(She's also waiting for answers on her questions and queries and updates above, though that could happen after we get the slab addressed.)

(Qivys: Make a Strength check with advantage.)

Gerrard:

Once the slab is dealt with, Gerrard says, “I think a foray into the above water entrance would be good, especially if we can benefit from some concealing magic as we enter.  I dare say our aquatic friends could use a rest after our battle with the Sahuagin patrol that burst in on us, so they may wish to stay below and be our lookouts for any foes approaching underwater.”