Wis Save: 3

"Aw, leaving so soon?" Sunshine taunts as she swipes with her dagger again as the harpy starts moving out of her range.

AoO: 5 Damage: 4

Telias takes a jab with the quarterstaff as well. 

Attack: 12 Damage: 7

Nalla,  you finally come to your senses, at the end of your turn.

Sunshine, your dagger swipes through the air, missing the harpy's feet, but Telias' quarterstaff finds its target, and the harpy has a nasty bruise.

Sunshine and Telias are up (with your actual turns, not your reactions).  The harpy is now thirty feet up in the air again.

Telias taps his staff on the deck again and the sound of a massive bell echos around the harpy. Toll the Dead (DC12 Wis or 7)

With a grumble, Sunshine pulls out her short bow. "Couldn't just stay on the ground, huh?" she mutters as she nocks an arrow.

Attack: 12 Damage: 6

Harpy 2 WIS save:  11

Telias, your spell fails to take hold.  However, Sunshine's bolt does hit the creature.

Harpy 1 attacks Mr. Fists again:

Claw Attack: 14 Damage: 7
Club Attack: 5 Damage: 2

The creature clumsily fails to make contact, and the crew take the opportunity of her distraction to make their escape below deck.

Verdan and Nalla are up.

Very angered by the fact she had been stunned by the noise, Nalla quickly turns her attention to the harpy that did it. With much less flourish then her normal casting she quickly moves her finger and mutters, blasting it with three bolts from her Magic Missile spell.

(For ease I am just going to roll 3d4 +3 since it is all at the same target.

Magic Missile: 

11

thunk thunk thunk

The magic missiles hit their target, but she's still up.

Verdan is up.

Verdan draws his shortbow, hoping to down the harpy.

Attack: 12 Damage: 9

"Now finish off this loathsome beast, 
and on its wings tonight we'll feast"

Bardic inspiration (1d6 on an attack roll or saving through) to Sunshine.

Verdan, you do manage to cut the harpy down.  The body crashes onto the deck with a very final thud, and there's a squawk of outrage from the other creature.

Round Four:
Mr. Fists, Sunshine and Telias
Harpy 1
Verdan and Nalla

Mr Fists, Sunshine and Telias are up.

Mr. Fists will attack the harpy.

Short Sword Attack: 13 Damage: 6

Bonus Action Unarmed Strike - Attack: 11 Damage: 4

Up close, the harpy seem less agile than it might in full flight; both blows hit, one to the wing, one to the legs, pummelling the creature and affecting its balance.

Sunshine and Telias are up.

"Yeah, that's how we do it!" Sunshine grins at Verdan before remembering, oh, yeah, there's two harpies. She quickly heads for the stairs on the ship, nocking yet another arrow as she scurries up and taking aim at Harpy 1.

Attack: 20 Damage: 4

It's a skilful strike, as Sunshine's arrow hits her wing; she remains in the air, but you can see it pains her to fly now.

Telias is up.

Telias closes the distance and summons more spectral bells to fill the air. Toll the Dead (Wis DC12 or 7 damage)

Harpy WIS save:  17

Whatever the harpy hears, it seems not to bother her.

The harpy, seeing her comrade dead, will disengage (to avoid Opportunity Attacks) and fly forty feet away.  She seems to be fleeing.

Verdan and Nalla are up.

Nalla will move e to the other side of the ship to try and get the harpy in range of a Firebolt, blasting at it if she is able.

Firebolt: Attack: 18 Damage: 5

Nalla, your spell seems to misfire, and a bolt of flame fires off, arcs and drops into the ocean.

Verdan is up.

Verdan sighs, lining up another shot with his shortbow.

Attack: 16 Damage: 7