((The undead phased through the walls, so nothing for Petmailer to disengage from, if he'd like to otherwise use his action for something.))

Stena retreats into the fog, calling for Galingal, while fitting another arrow to her bowstring. She's deep in the fog, so wouldn't be able to see anything to shoot it... but hopefully nothing can see her either... unless they can sense her presence without need of vision.

Galingal can hear someone speaking what sounds like Stena's voice from the fog, some 20 feet behind him.

The drow stumbles past Lia and Neth up the stairs to where a rather frazzled looking Kolose is just finishing getting smooshed against a wall.

Lia begins casting, holding her spell for when the undead return.

Initiative:

Neth: 23 (readied dagger)
Stena: 22  (readied arrow)  
Petmailer: 20 
Lia: 20 (readied VM)
Cows: 19
Yuk Yuk: 19 (readied dagger throw) (up the stairs)
Spiderbait: 14 (readied dagger throw) (up the stairs)
Kolose: 13     <------<<<
Galingal: 12   <------<<<
Fargas: 12 (readied hand crossbow) (up the stairs)
Jimjar: 8 (readied hand crossbow) (up the stairs)
Coffin Residents: 7 (No longer Turned/No longer Turned/X/X) 

Kolose curses softly, muttering something about instability, even if he can't help interrupt his rambling with the occasional, muted "Fascinating!" in between it all. The statement of how dangerous it is to be casting magic is the part that is said out loud however, as he does a quick mental tally... And then realizing he's still looking good while others are not, rushes down.

"Stay clear, who knows what may happen next time!"

(What does Kolose see shifting as far as possible? Or until he at least sees hostiles?)

Kolose passes Neth and Lia on the next landing down, and peers around the corner down an empty flight of stairs other than the pile of cow carcasses half in the fog. No Stena or Galingal to be seen.

"They've been coming in and out of the walls! This is NOT fine!", Neth imparts.

Petmailer’s action is to dash up the stairs, saying “We need to leave this place and seal it shut!  I have no way to kill these ghosts, they are already dead and my bow doesn't really do anything to them!  We will all die if we stay here!”  He calls to everyone to flee with him.

Kolose will hold the stairway for now, preparing another toll the dead as he shouts down.

"Come on, we have to leave!"

Whether he will cast his spell depends on a few factors however. Most notably, he's hoping that the two behind him would rush up the stairs before any ghost appear, or for him to hold the spell until they do. So that if he DOES blow up again, he doesn't blow them up them as well.

Galingal turns from where he was about to investigate the cracked coffin when he hears Stena call his name.

He moves back towards the fog, looking for Stena.

"Where are you?" Galingal asks. 

If Stena is visible, Galingal will see the state she's in and cast cure wounds  healing the dwarf for 8  

But if he can't see her, Galingal will keep his rapier at the ready while he searches.

((Stena is still within the fog, so not visible, Galingal was right at the edge of the fog. Is he entering to fog to try to find her? (Cure wounds doesn't need to be able to see, only touch.).))

Petmailer flees upwards, bumping into and receiving guttural curses from who must be the invisible goblins.

Kolose begins casting, in preparation of unleashing it on the undead.

Galingal calls out to Stena (let me know if he'd move into the fog to try to heal her, or hold rapier ready, or use his action to search the tomb).

"Behind you!", Lia shouts at Kolose, pointing at the undead that has appeared between the two of them. He can also see the other glowing one has emerged from the wall near the fog, and without Stena as an easy target, orients on him.

There is a twang of a crossbow as Jimjar appears on the landing, his invisibility lost, and Neth hurls his dagger at the undead.

Jimjar Handcrossbow Attack: 19 Damage: 8

Neth Thrown Dagger Attack: 18 Damage: 7

Both attacks pass through, doing minimal damage, but tearing away a few wisps of incorporeal undeadness.

"Leave him alone, you unlaundered, crusty sheet!", Lia utters, the crystals pulsing as she imbues her words with magic. 

"Aww, beans, that didn't work, I really hoped to insult that jerk! Kolose, see if you can end it, pop this fool like a juicy zit! Wait, why am I speaking in rhyme? I truly hope it goes away in time..."

((Is Kolose casting Toll on one of them?))

Initiative:

Neth: 23 
Stena: 22  (readied arrow)  
Petmailer: 20 
Lia: 20 
Yuk Yuk: 19 (readied dagger throw) (up the stairs)
Spiderbait: 14 (readied dagger throw) (up the stairs)
Kolose: 13 
Galingal: 12 
Fargas: 12 (readied hand crossbow) (up the stairs)
Jimjar: 8 
Coffin Residents: 7 (No longer Turned/No longer Turned/X/X)  <------<<

((Kolose, give me an Arcana check please?))

Arcana: 14

Kolose, on the cusp of casting the spell, is struck by a suspicion that necrotic damage won't have much to act on with creatures that have no physical form...

Kolose curses softly, he KNEW this, but why did it come back to him only when face to face to one of these things?! He stands still for now, bracing himself. He's going to try and keep concentration on the spell, just so that maybe he can trigger it after all the others got further up the stairs!

Never having heard Stena say she 'needed' anything before, Galingal would interpret that as a sense of urgency and he would move into the fog to search for her, hand out until he found the surly dwarf.

Galingal reaches out for an unseen Stena in the fog, feeling a bit like he's reaching into a hunting trap as he tries to make contact with the prickly dwarf.

He ends up poking her nostril, which all things considered, could have been worse, and is able to make contact to heal her.

((Stena gains 10 HP.))

Kolose holds his ground as the undead drifts rapidly towards him and swipes at him with its spectral hand.

Attack: 12 Damage: 3, DC 10 CON Save.

After it attacks, it flits for the wall.

The other undead drifts up the stairs, lit up by the extra glow of Petmailer's faerie fire, but similarly vanishes through the wall, not quite able to reach Kolose to attack, and opting to bide its time.

The hand passes through Kolose, his breath catching in his throat as he feels rather unwell.

((Two DC 10 Con Saves please, first will be for the attack and max HP reduction, second will be your concentration check.))

"That was my only dagger, magic's all I've got left!", Neth says worriedly at Kolose. He falls back slightly up the stairs, dragging Lia with him, but keeps the elderly wizard in sight to be able to snipe at the undead when they reappear.

((Petmailer is about a floor up from the stairs heading down into the tomb chamber, so would be above the upper right portion of the above image.))

Initiative:

Neth: 23 (readied EB)
Stena: 22     <------<<
Petmailer: 20     <------<<
Lia: 20 
Yuk Yuk: 19 (readied dagger throw) (up the stairs)
Spiderbait: 14 (readied dagger throw) (up the stairs)
Kolose: 13 (readied TtD)
Galingal: 12 
Fargas: 12 (readied hand crossbow) (up the stairs)
Jimjar: 8 
Coffin Residents: 7 (No longer Turned/No longer Turned/X/X)

Petmailer dashes upward, fleeing from the ghosts and calling out to the others to do the same.

Petmailer is all alone on the stairs, he thinks he passed the goblins somewhere along the way, but the only thing he can hear at the moment is his own labored breathing.

He makes it to the first landing, and is able to see up into the room they first entered from the tunnel.