Melanthios will fire at zombie 3.

Attack: 19 Damage: 15

Proving to be a lethal sniper from his hidden location, Melanthios drops the zombie; it violently crashes into the water and begins to float downstream toward the city.

Anzir, Irma, Koris, and Hana may act, in any order. Zombies #3 and #4 are terminated. 

Anzir hefts his war pick and drives it down on Z2's head.

War pick Attack: 11 Damage: 9

Anzir's pick drives its way entirely through the zombie's head, striking the stone path underneath with a sharp clank. Remarkably, the monster fights on, its eyes glaring at the paladin that looms above...

Actions for Irma, Koris, and Hana are next. The undead will follow. 

Koris pulls a knife and runs up to try to finish off Anzir’s zombie problem

Attack: 22 Damage: 6 

Koris drives his blade into the zombie at Anzir's feet, but this is one reanimated corpse that will not surrender. The zombie continues to groan and writhe, its mindless drive to kill and eat remains in tact...

Actions for Irma and Hana remain. The undead will follow. 

Irma shouts out, "Thank you!" to whoever it was that killed the zombie in front of her. She pulls out the arrow stuck in her side and says, "not today" (casting Healing Word on herself for 4 health)

She then backs away from the skeleton, next to zombie #2 and leans down over it, whispering "salad" to it (casting another Word of Radiance for 2 damage on CON 12 saving throw). If the zombie falls dead then she'll back off even further and drop down behind her shield to avoid any further arrows (mechanically: fall prone to impose disadvantage on ranged attacks).

Irma's spell has no effect on the zombie; Hana sees this and extinguishes her first bonfire and creates a new one atop the relentless zombie...

...the flames engulf the monster, yet somehow it escapes death's grasp. With its clothing rags ablaze and putrid flesh now smoldering, the zombie lunges again at Anzir...

• Melee slam attack: 18 | 2 bludgeoning damage

The bow-wielding skeleton (#1) draws another arrow, and this time takes aim at Hana...

• Ranged shortbow atttack: 15 | 4 piercing damage

...and for a second time, the skeleton opens its mouth, simulating laughter as its arrow catches the druid in the shoulder.

The three Chultans nearest the bow-wielding skeleton rush in with clubs and shortswords, hoping to bring the monster down. Even through the deafening sound of the rainfall, the sound of the skeleton's bones being shattered can be heard.

All players may act, in any order. Current situation is as follows:

• Zombie #2 remains prone, is wounded beyond belief but rages on
• Skeleton #1 is now severely wounded and engaged in melee with three Chultans
• Skeletons #2 and #3 have shortswords drawn and are engaged in melee with Chultans
• Skeleton #4 has advanced and has a shortbow in hand

Melanthios will fire at skeleton 4, still going for the most vulnerable spots.

Attack: 20 Damage: 19

The most unnecessary crit damage of all time: 1

Poole drops her bow and pulls a shortsword from her back and a dagger from a sleeve, deciding not even to try to be the sharpshooter Melanthios obviously is. Her dagger aims for the back of the skull of S1, and the shortsword goes for it again, but if it drops, she'll spin around and aim for S2.

Sneak attack for one of them given it's in melee and S1 is flanked...

BA Offhand Dagger Attack: 24 Damage: 4 sneak attack 6
Shortsword Attack: 19 Damage: 6 (if this is on S2, ignore second roll)

Well, Irma tries "porridge" again, Word of Radiance for 6 damage. (it's radiant damage and should go through the undead fortitude in theory, if it fails the initial con save) 

Within seconds, three more undead fall. Melanthios's arrow drops the advancing skeleton (#4), Poole's dagger drops another skeleton (#1), and Irma's spell finally ends the zombie's (#2) run of luck.  

 Poole's shortsword then cleaves into another skeleton (#2) as the rogue finds herself fighting shoulder to shoulder with one of the locals. 

- - - - - - - - - - 

Anzir, Koris, and Hana may act, in any order. Remaining undead are skeletons 2 and 3 and zombies 5 and 6. 

"Stay down," Anzir growls to the zombie. Seeing it doesn't move, he peers into the downpour for more trouble. They are all far down the road. So he starts slogging through the mud and water along the north side as far as he can, keeping out of the bonfire as he goes.

Koris rushes down the street towards Skeleton 2 (dash)

Irma stays with Anzir, seeing as some healing might be needed soon.

(Also, I forgot that Irma is Life cleric, so she's actually full HP after healing herself couple of turns ago) 

Hana trudges against the current toward the remaining undead...

The skeleton (#2) near Poole drives its shortsword through the stomach of the Chultan, who then crashes into the torrent of water. The same fate befalls the locals who are engaged in combat with skeleton #3 and zombie #5. Zombie #6 limps its way forward, losing its footing as it does so. On its back, prone, it picks up speed as it is carried by the flow of mud and water. 

All players may act, in any order. 

Melanthios stays where he is, and fires again at whatever skeleton is the least injured.

Attack: 10 Damage: 17

Seeing the skeleton strike down a Chultan, Koris lunges forward to strike at the skeleton2

Attack: 16 Damage: 4 

Poole screams "Noo!" as the skeletons and zombies carve through the locals. "This town's not safe," she spits, through gritted teeth, eyes boring into the skeleton in front of her. "For you."

Her blades dance and try to behead the skeleton (S2) Koris is now engaging (and if successful, target the prone zombie Z6).

Attack: 12 Damage: 6 
Offhand Attack: 18 Damage: 1

Sneak attack damage1
Extra attack roll for second attack in case target is prone zombie: 16

She's not comfortable being at the head of the pack, but she doesn't have much choice at the moment.

Irma gets a bit closer and casts Toll the Dead on a damaged skeleton for 9.