Bob runs up next to Gillain, slinging his quarterstaff on his back as he runs. He nods at her once and claps his hands together, speaking ancient druidic words. A thunderous blast of sound and fury bursts from his hands toward the undead; it was just as cacophonous as if the heavens themselves had descended and thunder was booming right in front of them.

Bob casts Thunderwave at all the undead in a 15 foot cube starting in front of him. Any that fail a DC 14 Con save take 16 thunder damage and are pushed 10 feet away from Bob. Successful save is half damage and no push.

Tio will head out to the back door dashing as her action then spend her last ki point to dash again to try and catch up to whatever has Ireena.

 [current movement is 120ft]

Gimble:

Still leaning desperately on the brace holding the door to the vampire shut, Gimble sees the horned undead approach from a distance.  He calls down the cold of the far north, trying to freeze its wet bones and encase it in ice to slow its attacks.

Frostbite DC 13 Con or Frost Damage and Disadvantage on next attack:  1

Bob races to Gillain's side and cast his spell:
U9 save: 8
U10 Save: 13
U11 save: 20
Thunder and force roll from Bob's hands. 2 of the undead fly apart, scattering bone and rusty armor15 ft. away. The third undead crumbles into a pile of bone and old armor where it stands.

Current map:
https://docs.google.com/drawings/d/1AqpOMOQEjtOvC3uhtiBI4mqwFbXlf4upgKP8yPtM3MM/edit
DM: arrow on the map indicates the direction the new threat is coming from.
-Gimble can not see this from his position.

Tio rushes out the back door and almost immediately locates Ireena walking some 15 ft. to the northeast of Tio's location on the map.
A flash of lightning and two cracks of thunder, one from the sky and one from the front of the church are almost deafening. The rain, coming down in a violent deluge, make visibility hard for all those outside. 
Ireena's movements seem blocky and slow to Tio.

Inside:
Gimble and Ban are at the door. There is a violent push on it. Duro is trying to force his way out.
DM: Need a strength roll from Ban & Gimble to keep the door closed.

Front Courtyard:
The horned undead's movements are slow. It does not reach Gillain or Bob this round.

DM: Actions and requested rolls, please.
Understand the weather is a major factor in any actions/attacks, currently. 
Attacks are made with disadvantage due to the heavy rains affecting vision, grip, etc.. and the slippery conditions.
Any running will require a Dex roll to keep your footing once outside. 

Gimble:

OOC:  Since Gimble could not see the target of his attack last round, let us say he readied that action to inflict on any new active enemy that revealed itself.

"Stay in there, Duro!  We will get to you when the current emergency is dealt with," says Gimble, somewhat uselessly trying to reason with the hungry dead.  Leaning hard into the brace, he tries to keep the door shut so they don't have yet ANOTHER foe to deal with in this defiled church.

Strength Check:  17

Ban reaches down to pull another dagger but gulps hard as she regrets losing her stock at the mansion. With events unfolding from bad to worse, Ban begins to worry. Barely able to see two friends, entirely unable to see another, and literally trying to hold back danger with yet another, she starts to become increasingly concerned as she looks at the nearby fallen priest. Quickly, she picks up her bedroll and rope. Planting her feet, she presses against the splintering door and hastily says to Gimble, "I dunno how much longer the door will hold. If he breaks his way out, I'm gonna wrap him in my bedroll and tie him up tight."

Strength check: 12

Holding action to attempt to grapple and secure the boy with her bedroll. 

Gillain stands fending off attacks from the three skeletons just as Bob comes up beside her and blasts them all to smithereens with his powers!

”Wow!…”, she just about manages, “Thanks!!…”.

She looks up at the rows of rotting undead not moving, and then at the giant horned-undead, approaching.

”Back to the church, I think!… GO!!…”, she says to Bob.

So she doesn’t leave Bob, she’ll go no faster than him. If 25ft will take her to being just stood exactly central in the main church doorway, that would be great. She wants to try and block the doorway in an attempt to not let anything (except Bob) past ((She can reach 5ft all around with her spear, and has an attack-of-opportunity against anyone entering her reach, from polearm master)).

Finally she says in little more than a hoarse whisper, almost to herself standing in the church doorway, and to everyone else holding the priest’s son back, “Hold. The. Door… … “.

DEX check (if needed): 16 

Bob stood silent and staring in the aftermath of the thunderous shock erupting from his hands, bits of bone and rusting armor harmlessly scattering before the next row of unwavering undead. Gillain's voice got him back to his senses. "Ye doon' need t' tell me twice!" 

He runs alongside Gillain, eternally grateful that she kept up with his shorter stride. 

Dex check: 19

Duro Strength roll: 22

Duro presses on the door but Gimble & Ban are able to keep the door shut, by the slimmest margin. 
(Their combined was 23....:O)

Round 5: 
Bob & Gillain retreat, making it to just inside the doors of the church.

The undead move towards the church but at a slower pace.

Tio catches up with Ireena, in the cemetery.

Ismark comes stumbling toward the front of the church, where the rest of the party is located and asks: "Have you seen Ireena?"
He looks dazed and there is blood slowly dripping from the back, right side of his head. 

Duro screams from the other side of the door. "I am so hungry"

Actions?
Notes: Currently the party is out of combat, save for Duro trying to get through the door.

As Ban grunts and pushes her all against the door, she barks at Ismark, "A little busy, if you can't tell! You're a man, yeah? Be useful and do something."

“Ireena! We must go back inside, please come!” Yelling over the heavy down pour Tio will take Ireena and make their way back to the church slowly as to not fall in the mud. “Ireena talk to me are you hurt anywhere?” Her Astal arms are still going and very present. 

Gillain remains in the entranceway. Standing guard, for now. Spear and shield ready. “Can you hold that door? Are you all okay?”, she calls back over her shoulder...

The Cemetery:
Tio grabs Ireena and starts to lead her along. Suddenly Ireena stops: "What...What....where am I? Where is Ismark?" she asks as she starts to jerk her arm away from Tio. 
Almost miraculously, the storm clouds dissipate, the rain ceases, and calm returns to the area. 
The overcast remains but lightens to its normal dull daylight. 

Inside the Church
Ismark, seeing Gimble and Ban trying to keep the door shut, lends his strength and elans on the door. from inside the door, Duro tries to push it open but the efforts of the party keep the door shut. 

Abruptly the winds stop blowing, the rains cease and the storm disappears within seconds.

Gillain and Bob, from their positions just inside the church, look out and see the second wave of the undead turn towards the village and starts walking. As they march, the air around them becomes filled with black floating flakes, like ash. These flakes fly up from the undead and within seconds the undead disappears. 

The only evidence of the day's events are large pools of standing water in spots and ashes blowing on the slight breeze. 

As Ireena tries to jerk her arm a way, Tio’s grip tightens. “My apologies but your brother Ismark is back in the church...” Her grip not loosing “It seems you’re a bit confused, you were wondering off in a daze. Are you injured anywhere?” 

Tio stands in place waiting for a response, contemplating “The attack was a clear distraction so that they could take Ireena but who injured Ismark? Was it her?”

Insight: 5

Gimble:

Looking around, Gimble suddenly notices the dead priest, his skull pierced through by an unlucky (for him) skeleton arrow.  As the banging against the door continues, he says, "Uh, what do we do now?  The priest has been killed by the undead, and his son appears to be well on his way to becoming a vampire, if not there already.  Anyone know how to stop someone from transforming into a vampire?"

Religion:  13

Gillain sees the clouds break… and the undead vanish… and she drops to her knees on the steps… with a sound like a sack of chains hitting the rain-soaked stone. She takes a second, looking out over the now deserted churchyard…

Eventually she hears the sounds of the party moving and talking behind her, and starts coming back to her senses... She hears Gimble asking about vampires and she wracks her brains trying to recall… anything…

Religion or history check (both +4): 19 

Though Gimble and Gillain scan their memory for a way to "stop" a person transforming into a vampire, neither come up with a solution.

DM: Upon Gillain coming to the church, she used her Divine Sense to see if there was any undead or divine creatures within 60 ft. of her. Though there was a bit of interference, Gillain sensed there was a vampire on site. That being said, with the party's interactions so far with Duro....one would believe Duro is a Vampire, not changing into one.

Ireena responds to Tio's questions: 
"I have no memory of how I got outside. One moment I was standing with Ismark and the undead were at the doors of the church. The next I am standing outside with you, soaking wet."

Gillain remembers the clear smell of undeath she sensed when the party first approached the church. She stands and turns. Then walks, with heavy footfalls, back across the short hallway, towards the rest of the party.

With lead weights in her heart, she confirms plainly what the party had all been suspecting, “The priest’s son, is dead… I can sense it… … … All that remains, is a monster in his place… Beyond that door now… is a vampire!… …”.

“We can’t leave this thing here to escape and terrorise the town… it’s my duty to put the creature to rest…. …. Will anybody help me?….”

“... I understand...” Tio will loosen her grip on Ireena “You must be terrified, let us return inside.” Tio will escort Ireena back to the others. 

Gimble:

Sighing sadly, Gimble says, “So this Strahd creature sends back the priest’s son who has been transformed into a vampire.  The priest accepts his son back in an attempt to help him, defiling the holy ground of the church.  Now, the priest is dead from the undead invading the church, and his son is lost, with only his mortal shell left here, corrupted by the foul touch of undeath.  This is unfathomably cruel.”

Looking sadly at Gillain, Gimble says, “I will help,” as he backs up and prepares to cast more spells.