Gerrard:

     Abandoning the rope for now, Gerrard says to Oceanus and Peri, "Let's ch...ch...check the hold next."  Taking a deep breath, Gerrard dives for the hold and tries to open it up -- hopefully with help.

Athletics:  15

Kei

Waves breaking against the side of the skiff throw the small boat around. He struggles to keep his feet at times. "What can you see? Any floaters?" He enquires of whomever is closest to him. The boat rocks quite badly as a larger than average wave hits home. "Dwal! Keep it steady man!" He shouts at the dwarf, knowing full well it's not his fault.

Meanwhile, Trill continues to circle above keeping an eye on the group. Kei tries to clear his mind waiting to hear anything from his eyes in the sky.

Peri:

Peri resurfaces and takes a breath. "Can't hardly see anything down there. Ton of crabs." When Gerrard dives down to try the hold Peri will help him by wedging the crowbar under the hatch as he pulls. If he can get the crowbar in there, hopefully the other swimmers will be able to pry it open.

With Peri's help, Gerrard manages to wrench open the hatch. A little bit of oily residue escapes. Gerrard can't see a thing in the blackness within, but Peri confronts the bloated face of a week-dead corpse staring back at him, deeper within the hold. It's a horrific sight, but not an immediately threatening one - it's just a dead human body. But only one. There are no additional victims to be found here, nor much else here but a haul of rotten fish. 

Gerrard:

Unable to see below, Gerrard draws his rapier and soft moon glow fills the hold—making the corpse seem all the more spooky.  Nonetheless, Gerrard moves towards the body and tries to start pulling it up to the surface with Peri’s help.

Athletics with Advantage:  6

Even with Peri's help, Gerrard can't quite manage it. The body is bloated and twisted and misshapen and just won't fit through the small hatch– either you need an additional helper, or this body will need to come out in pieces. This hold was intended for fish, not humans; it's a tight squeeze through the hatch. It's an odd place to find a sailor.

Peri:

Peri heads back to the surface for another breath. Puzzled at finding one of the lost sailors in the hold, he looks at the boat on the way up to see if there's any sign of an attack (arrows, claw marks, etc) Perception 19. "Must have been a good reason he'd crawl down in there..." he thinks. 

Popping back up above the surface he reports, "We found one of 'em in the hold -- strange place for 'im. Toss me the net so we can bring him up. When we've got him in there, I'll give 3 hard pulls; that's your signal to hoist him up."

Gerrard:

Following Peri up to the surface and getting a deep breath, Gerrard hears the plan and asks, “Get the net on him Horst, then pull him through the hatch?  We can guide while those on the boat provide the pull.”

Diving back down with Peri, Gerrard prepares to enact the plan.

OOC:  will this be more of acrobatics to maneuver the body as others provide the pull?

Kei

Them rocking of the boat eases a little. He puts one hand on the gunnel and passed the net to Peri. He ties of the rope to one of the oar holders. "Three tugs. No problem". Turning to Dwal "Hold it still, they've found one of the bodies". He sits as close to the edge as feasible with one hand on the rope, waiting for the signal.

Peri:

Peri nods to Gerrard. "I was just thinkin' we'd need the net nearby to get him up to the boat, but I like your idea better. With them pullin' and us maneuverin' the body out, he should make it up fairly easily." He looks to Kei. "When we give the signal, pull real nice and gentle. We don't want him wedgin' in there and you tryin' to pull the skiff down to meet us." Peri dives back down with the net. He works with Gerrard to try to wrap the net around the body. If they get him wrapped up he gives three firm tugs on the rope and helps guide th body out of the hold.

((OOC: I'm okay with you rolling whatever checks you think are appropriate here -- I'm not sure what the DM Guide has to say about skill checks to haul out a corpse. Since we're working together I hope the "Disinter" check can be made at Advantage.))

Peri notices a couple of serious gashes under the starboard side, as if the vessel had struck a rock or vessel before sinking. In addition, there are lots of superficial marks all over it, perhaps the work of the vast horde of crabs.

Taking slow, deep breaths, Peri and Gerrard dive down again into the icy, black water, this time with the net, trailing rope behind them. Oceanus continues to swim around the wreck in a large circle, his trident out. His attention is elsewhere, and he makes odd clicking sounds.

Peri manages to slip through the hatch into the cloudy, fishy hold, and quickly lash the net around the foul, distorted corpse. Three tugs later, Dwal and Kei begin to slowly haul in their catch, as Gerrard and Peri try to coerce the sailor through the hatch.  Gerrard - acrobatics check with Peri's help:  12 

Success! The netted sailor comes out in one piece. Dwal and Kei begin the quick work of hauling up the bloated body.

That's when a pressure wave rocks the five of you, even rocking the already unsteady boat above. A wall of cloudy water engulfs the submerged party members.

For the huge boulder - a smooth-domed rock some twenty feet in diameter - is, in fact, no rock at all. To your horror you suddenly realize that it is the shell of a massive crab, which is right now pulling two gargantuan claws out of the sand below. With surprisingly fast reflexes, it lurches forward and grasps for its prey - one claw for Gerrard, the other for Peri.

Initiative:
Massive crab:  11
Kei:  14
Gerrard:  16
Peri:  20
Dwal:  17
Oceanus:  21

The netted dead sailor is still in the water - it hadn't quite been hauled in when the huge crab attacked. 

Already on guard, Oceanus gets the jump on the armored crustacean. Holding his trident with both hands, he tries to plunge it into the claw about to grasp Peri.
Trident attack: 7  Piercing damage: 3

 Oceanus' trident manages to successfully puncture the claw. He sinks it deep into the huge appendage.

Everyone may act before the huge crab.

Peri:

He squeezes out of the foul hold behind the decomposing corpse. He begins slowly rising toward the surface alongside the body when the enormous crab bursts from the seabed and attacks. With the silt stirred up by the beast's claws he knows visibility is going to be a problem, so he looks toward the crab and casts Faerie Fire (DEX save, DC 12), careful not to include his comrades in the spell's Area of Effect. He kicks upward to the surface, taking in a deep breath since it might be his last for a while, turns over and dives for the seafloor to avoid the beast's pincers.

The massive crab tries to violently dodge Peri's eerie violet fire: Dex Save: 10

 ...but cannot evade the glowing light. Many of the small crabs on the sea floor are similarly afflicted with purple light. The boat flails in the added churn of the massive crab's sudden movement amidst an already quite choppy sea. Dwal and Kei struggle to keep their balance. Acrobatics rolls: 2 and 8 

Kei falls prone in the boat; Dwal falls out of it altogether into the bitter cold ocean. Dwal, Gerrard, and Kei may act next (neither Dwal nor Kei may reach the crab this turn for a melee attack.) Visibility is extremely poor within the cloudy water, and even worse from the surface, but the massive, glowing crab is plainly visible to all with its intensely purple glow. 

Gerrard:

Enhanced by the magic armor, Gerrard surges to the surface and manages a quick but deep breath as he breaches, then dives back down rapier first, surging forward like a swordfish straight at the most vulnerable chink in the giant crab's carapace!

Elegant Noble's Rapier:  Attack: 23 Damage: 10

Main Gauche:  Attack: 16 Damage: Unable to parse dice roll.

Action Surge Rapier:  Attack: 19 Damage: 7

OOC:  Riposte if missed by the Crab, Parry if hit by the Crab (will post reaction later).

Dwal

Spitting and sputtering Dwal tries to get back to the surface and the boat. Upon seeing the massive crab Dwal mutters: "Now there's something you don't see every day." 

Dwal's only action will be to cast Magic Missile at 2nd level.

Missile 1: 2
Missile 2: 3
Missile 3: 3
Missile 4: 5

Dwal will swim to the boat after casting it. 

Kei

"Bloody crustaceans!" He curses as he falls. Upon standing he sees the purple glow of the giant see creature. "Dinner is served gentlemen" He casts Toll the Dead on the giant crab quickly followed by Shield of Faith directed at the small unarmoured halfling just as he dives under.

((Dmg 2. Wis save 12))

Dwal fires a quartet of arcane darts of brilliant energy at the massive glowing crab, drilling blackened holes in its thick armor. He scrambles back into the rocky skiff.

Gerrard surfaces like a leaping porpoise and then dives deep again. He flashes his blades through the water as if it were nothing but a thin mist, lopping off a leg and and an eyestalk, then plunging his rapier deep into its soft innards. A thin stream of yellow blood leaks into the already thickly clouded water, but still the massive crab advances.

Kei's magical bell makes it pause for a moment to reconsider its advance - Wisdom save: 1

...but it shrugs off his dangerous illusions.

One enormous claw jets out to grasp Peri:
Claw attack: 11  Bludgeoning damage: 23

 Even with Kei's magical shield, the claw successfully grabs Peri. Ribs audibly pop as the massive claw nearly crushes the life entirely out of the trapped halfling. (Peri is grappled. Escape DC 15.)

The other claw attempts to snag Gerrard:
Claw attack: 8  Bludgeoning damage: 25

 Gerrard dances just out of reach. Gerrard may riposte.

(CON save to maintain concentration on faerie fire: 17)

Gerrard:

Dodging the massively powerful blow from the crab, Gerrard lashes out with his glowing rapier in response.

Riposte:  Attack: 18 Damage: 10 Plus Superiority:  8

Gerrard:

Seeing Peri writhe in the grip of the monstrous crab, Gerrard moves over and stabs twice in rapid succession at the claw holding his friend.

Elegant Rapier:  Attack: 19 Damage: 9

Main Gauche:  Attack: 25 Damage: 8

OOC:  Party or Riposte as before...