The darts borrowed deeply in the hide of the hound and already quite wounded H1 died with a final wimping sound. The devil and slightly hurt but very much alive H2 looked as if they were going to continue the fight.

Polly?

Polly will go out in the corridor and position herself in the corner behind Adrey and. Then she sees the dog and devil form between choir and Adreys legs, she raises her wand of secrets and let out “Magus oro!” And let lose 5 magical bolts of pure energy! 3hits the dog and 2 on the devil! Then she take a look down the corridor.

magic missile lv3: 
dog: 4, 3, 3, 

devil:5, 4, 

(Posting Ordrag's next actions in advance)

Not seeing any immediate danger to the north, Ordrag will leave it to those already watching and return to the tunnel entrance and speak to one of the clerics. Hey priest, how come yous all aren't getting out of here?

"The tunnel is no more," tiredly answered one of the man, "it opens up to the abyss beyond".

"We thought to flee the devils, but got ourselves cornered in this crypt," stepped out a haggard woman, her grey hair matted with sweat. With one arm, she clutches a leather-bound tome to her breast. In the other hand, she wields a ceremonial mace that would probably shatter if it struck anything harder than a pillow. "The only way out is back through the stairs and main Cathedral. But it is full of devils!"

Meanwhile, still force darts sent by Polly visibly hit the hound, yet did not seem to cause any harm, instead, the devil looked as if it got full blow. In her mind Polly heard a screem, full of pain and hatred. The hellhound jumped forward, opening itself to the attack of remaining dwarves, and breathed out flame: 22 (Choir, Adray, Polly - Dex save DC12 for half damage).

The devil stepped forward right behind the hound. His long arms and huge halberd allowed him to reach Choir over the hound and just self-repaired Brutus:

Devil vs Choir: Attack: 16 Damage: 8

Devil vs Brutus: Attack: 21 Damage: 10

Choir, nimbly dodged the weapon, but Brutus got a huge hole on the side.

Players turn.

Ordrag's natural inclination is to look to the captain and follow orders, but no-one here seems to wield that kind of authority. He looks dubiously at the woman and asks: Er, are you in charge? I heard you had some duke from Baldur's Gate defending the city.

(Choir's dex save: 13 )

Revenge: Wrath of the Storm. The hound must make a DC16 save for half damage, or take 9 thunder damage.

Evading the worst of the bad dog's bad breath, Choir attempts to bonk it on the head with her magic mace. Attack: 19 Damage: 10

"Not in charge - no, but... all the elder priests are dead. I am just an acolyte. Acolite Pherria Jynks." The woman looks in the same time scared, tired and very determined to do her duty. "If you mean Grand Duke Ravengard, he took a group of guards to the city’s grand cemetery to investigate the proliferation of undead in that area. This is when devils attacked."

Ordrag can hear sounds of fight from the sough passage and other people around- those that are watching - commenting on development of the battle.

(Not trying to jump the queue, but I'm going to bed and lots tends to happen while I'm asleep, so posting ahead again...)

"We'll have to man the ropes till he gets back then", replies Ordrag. "You're probably safer right here than anywhere else I reckon." And with that he will run back to the north corridor and try to get in view of Lulu and the others, calling them to flee to the crypt in that direction while he guards the passage.

ooc: polly is supports to stans 3 squarepants back though. 

Polly save: 16

Adray reflex: 14

Adray sees the hound take a deep breath and he knows what's coming.  He higa the wall as best as he can to minimize the brunt of the blast.  He scowls while thinking a small hallway is a terrible place to fight something like this.

Not able to get around Chior, he again tosses two darts at the hound.

Attack: 27 Damage: 8

Attack: 18 Damage: 8

(Ah, that was the corner - then Polly can disregard the damage and attack at will)

Yay!

Seeing that the doggo didn’t take any damage, Polly doesn’t dare cast another magic missile at it. Instead she yell out “Hey doggo! Did you hear the one about the German sausage? It was the wurst!” And cast hideous laughter 

ps: what is down that corridor? 

(If possible, Choir is willing to swap places with Adray next round: he does much more damage, and she should probably not blow all her spell slots, not knowing what's coming up.)

 Hound's Dex save: 5

Adray was every bit good as a sniper, as he was a puncher - both darts hit, yet, both darts did not seem to affect the hound, nor was it affected - as it seemed - by Choir's magic. However, the devil again silently roared in pain.

Both were still standing, though.

Ordrag was signaling Lulu to come, and little elephant sent kids ahead, vigilantly hovering over them. When children turned the corner, behind the small group a came a strange clacking sound. And at the far end of the corridor Ordrag could see a creature seemingly consisted of clutching claws. Hard to say how fast it is, but Ordrag and Lulu definitely had only seconds to decide what to do.

Fran and Brutus

Fran will squeeze around the corner, muttering to herself about the tight corridors.

(If it's possible to position herself behind Polly and still attack...)

"Duck!" She'd call out to her party members as she'd release a pair of daggers.

Attack 1: 7 Damage: 7
Attack 2: 15 Damage: 7
Bless: 3

"Hang in there just a little longer Brutus! Vlorss!" Familiar gears whirr to life to mend the defender.

BA: Steel Defender Repair 2/3 per day: 5

Sorry, fresh map:

 And here was the full map: https://www.dndbeyond.com/forums/d-d-beyond-general/play-by-post/50210-descent-into-avernus-test-drive?comment=2089

(Okay behind Adray?)

Ordrag would certainly ensure the kids get past and into the crypt area to where the other people are. Then he will stay and guard the top corridor to protect the crowd from whatever is coming, and drink a healing potion if there is time. If Lulu wants to stay and help that would be welcome. And any others that came with the group that can fight.

(Fran can stand behind Adray, of course)

Fran's attacks were quite successful, if not in the way they were intended - the hound was still standing (though hurt), but the devil behind it dropped to the floor and soon was nothing more but a pile of dust.

Harkina used her bow and a silvered arrow again: Attack: 7 Damage: 5

The dwarfs, unable to reach the monster, threw an axes at it: Attack: 23 Damage: 8 and Attack: 17 Damage: 7

The heelhound, unsure which group to attack, growled: 4 It seemed out of it's fire breath, but the teeth of the fiend were strong enough. It lashed out on Choir: Attack: 19 Damage: 7 + 7

The attack was a complete miss, though.

Meanwhile, Ordrag, druid and Lulu watch the clawed and - as they could see now - heavily spiked monstrosity coming out into the corridor. It looked like a crab, but a crab from the most horrible nightmare - twisted and cursed, emanating waves of the silent madness. The clanking sound become louder and the group realized, that crab is not alone there.

Players turn, then all monsters. (Right now crab(s) are under H13 but would be happy to expand).

Choir, not afraid, but knowing there were better fighters in the group than she was, bonked the hellhound one last time ( Attack: 23 Damage: 12 ) then moves back, handing her mace to Adray as she does, knowing he has no magic weapons effective against demons.

As a bonus action, she casts Healing Word on Adray for 7