You were indeed fighting at the base of the stairs. The path forward leads you down the hall once more. The shadows creep along the wall alongside you, watching your every move and motion, metaphorically of course. You continue forward. The rain beats against the windows as thunder peals in the distance. The sound of a heartbeat fills the halls, distant at first, yet as you grow closer, the sounds build. This heartbeat is familiar, uneasing even. Cold, dark, like the sound of a twisted and broken clock forcing a heart into motion. The hall leads to another foyer, which climbs into a massive spiraling towered staircase. A mosaic floor adds a touch of color to the otherwise dark, cold, empty tower that rises above you. The spiral staircase rises slowly into darkness, hugging the outer wall. In the center of the room, another set of stairs leads down. Adanmar’s burning hate runs cold. You feel that you are right on top of it... or under it? One of the two.

Adadnmar Windblood

((From where the heartbeat is coming from? Up or down?))

From what you can tell, up. However, it seems to be omnipresent in this tower.

Adanmar Windblood

The Revenant lifts his chin "Upstairs" he says to the others almost growling. Adanmar start to climb up the spiral staircase towards the heartbeat sound. His hand on the hilt of the Sunsword as he sneakily steps up ((Stealth: 23)) and pays attention to not missteps in any rickety step ((Perception: 15))

Elwarith will nod at Adanmar, nock and arrow and follow him up the stairs

[Stealth: 25]

As Adanmar steps onto the spiral staircase, a reddish light flares high overhead, then settles into a dull, pulsing red glow which flares rhythmically to its own beat. You now see the full immensity of this tower. The spiral staircase circles up the tower’s full 200 foot height. The tower, sixty feet wide at its base, becomes narrower as it climbs. At the pinnacle of the hollow tower, a large crystal heart pulsates with red light. Above the heart, the stairs continue upward. At the pinnacle, you can see the faint shadow against the red light, a familiar vampire’s shadow. A voice carries on the wind, “We end our little game now.”

For simplicity, we’ll stick with the previous Initiative, which means that Elwarith is up.

However... Heart of Sorrow: 10

Elwarith

Davmorn

George

Heart of Sorrow

Viorela

Adanmar

Strahd. 

(oh shit)

Elwarith will continue to move up the staircase towards the crystal heart and the vampire.

(OOC - ideally the plan for me is to eventually get within my 150 foot range of the heart with my bow and then launch some arrows at it - I move 30 ft/turn and can use my cunning action to dash as a bonus action - if that'll get me close enough then I'll roll some attacks this round otherwise they will have to wait till next round)

You may certainly move into the range of the heart. Go ahead, try it. Haha!

(OOC - can I assassinate a crystal heart? hehe)

[Gulthias Longbow: 23 Damage: 10]
[Gulthias Longbow: 22 Damage: 6]

Unfortunately, the Heart of Sorrow is an object, not a creature! Which means that it takes a total of 12 damage from that. As the arrow strikes the heart, a flash of light pulses like a screaming wail. As it does, 10 Flying Halberds shoot up from the base of the tower and begin rhythmically moving around heart. One flies toward Elwarith, Attack: 17 Damage: 7 slashing damage. It spins itself around and now floats tauntingly in front of Elwarith.

Davmorn is next to act. He’ll begin moving up the stairs 30 ft. He raises a hand toward the Halberd, “Outta the way, ya blood-rusted hunk o’ junk!” As he does, a burst of Sacred Flame pours down on top of it, (Dex Save: 14) for 14 radiant damage. The blade shifts and wobbles, but still remains.

With that, George is up next!

George rage, grab halberd, hit other halberd? 

Athletics: 23

To-hit: 22

Damage: 11

The halberd in front of Elwarith is currently 60 ft from George. The others are 200 ft above him encircling the heart.

Quote from JcAndD >>

The halberd in front of Elwarith is currently 60 ft from George. The others are 200 ft above him encircling the heart.

 Okay, George Dash this turn, do that next turn. 

George runs past Davmorn! As he does, the rhythm of the Heart of Sorrow reaches its apex! The heart beats once more as the stairway seems to ripple with power. Elwarith, Davmorn, and George must all make Dexterity Saves: 11, 8, and 15. Both Elwarith and George manage to duck out of the way as the pulse of energy causes two sections of the wall to extend and knock them off of the stairwell. Davmorn, meanwhile, is not so lucky. A section of the wall strikes him in the face and sends him tumbling over the side. He falls to the ground, taking 17 (oops d6) 15 bludgeoning damage. You get the feeling that if he were prone or crawling, then the attack would have missed him. Concentration check: 19, Bless remains. Davmorn groans, “Just a heads up... The walls don’t seem to care for us.”

Viorela is up!

"The castle, no, the land itself is under the cursed vampire's domain," Viorela adds to Davmorn's statement. "Be on your guard." With that, Viorela rushes up the stairs trying to reach the dreadlord and the mysterious heart. She will dash toward them.

With that, Adanmar is up!

Adanmar Windblood

With a grunt, Adanmar embraces his longbow and fires at the halberd in front of Elwarith ((Attack 1: 25 Damage: 9; Attack: 14 Damage: 7)).

He spends the rest of the turn to go up the stairs.