The BFOAGWGH

Twiglet readies an arrow, intending to fire as soon as the others get the dark elf to commit as they come through the door

Initiative 20

Short bow from hidden (hopefully not completely ahead of myself) Attack: 6 Damage: 6

Adding second roll so I don't edit the first roll 25

And dash to a pillar with a good position as my bonus action

I don't think Ro will be able to get within melee range of the elf during the 1st round (or ambush round if we successfully surprise her) so instead she'll follow Twiglet, throw a dagger at the elf, and then use her bonus action to hide behind a pillar.

Attack: 10 Damage: 7

Advantage roll if Humblodt's spell works: 15

Hide (stealth): 16

Humblodt's intended actions:

1. Cast guidance on himself to boost his initiative roll by 1d4.
1a. Bonus action cast shillelagh.
2. Wild shape into a spider.
3. Enter the room with the elf. Stealth 20 (not sure if roll is necessary, but just in case).
4. From somewhere behind her (possibly behind a pillar), bonus action transform into a Humblodt. Initiative 22.
4a. Cast entangle centred on the elf (DC13 STR save).

Hopefully (4) is a surprise round.

Note that the room area of effect is difficult terrain (20' square), so will slow movement for everyone, including the elf even if she makes the save (unless she can damage Humblodt enough to break his concentration).

Once the spider has transformed back into a dwarf shape, Xiaolong will sprint, taking advantage of the elf being surprised, to attack, while screaming to gather and release her internal Ki.

Initiative 23

Shortsword Attack: 11 Damage: 5

Flurry of Blows:

Unarmed Strike 1 Attack: 18 Damage: 7

Unarmed Strike 2 Attack: 13 Damage: 6

Dark Elf Perception (Disadvantage because she expects to be safe) 13

The Dark Elf is surprised as vines sprout from the rocky floor entangling her.

STR check against entangle 12

But she tears herself free and reaches for her staff which is sitting beside her

Dark Elf Initiative 12

XiaoLong rushes through the door swing her sword which the elf dodges, but Xiao's flurry of blows slip past her defences and striking her chest.

She recovers her balance evading the dagger and arrow coming at her from Roars and Twiglet.

(Tallanvor has a surprise round)

Humblodt will attempt to snatch the staff: Dexterity 12

 Ro jumps onto the table and hurls herself at the dark elf's head. She wraps herself around the elf's face, grabbing a fistful of hair and one ear to latch on,  and attempts to jam a foot into their mouth.

Acrobatics: 22

Humblodt tries to grab the staff before the elf does, pulling it out of her reach.

Elf Dexterity check 4

Meanwhile Roars leaps at her head trying to stop her speaking. Her foot jams in the elf's mouth and her body blocks her eyes.

Elf Acrobatics check 16

(Have advantage on your attack rolls as long as Roars holds on)

With Ro clinging to the dark-elf's head, Humblodt snatches away the staff. Twiglet can't get a clear shot with his bow, so he draws his short sword and, careful to stay out of the elf's sight-line as she grapples with the goblin, he slips close and attempts to ham-string her

Attack: 25 Damage: 14

Twiglet's attack slices open her legs causing her to fall to the ground with a scream. Roars manages to hold on. She is continues to scream furiously as blood pours from legs.

With no free hands and one foot stuck in the elf's mouth, Ro is going to try to bite the elf and kick it in the ear with her free foot.

Bite Attack: 11 Damage: 0

Kick Attack: 14 Damage: 0

It's...not very effective.

Tallanvor Initiative: 0

Tallanvor adds to the fury with a mighty swing of his mace: 11 Damage: Unable to parse dice roll.

Damage rolls

First attack:5

Tallanvor hits the struggling elf on the head with his mace and she falls unconscious and stops fighting against Roars. Roars continues nibbling on her ear regardless.

"HO HO, she went down like a sack o turnips!" Tallanvor laughs

He ties up the elf so that she won't be able to move struggle so that he can bring her out of the cave. He makes sure her mouth is gagged so that she won't be able to utter any spells or cry out for help. "I reckon once she comes around we can get her to talk" He says with a look at Ro's daggers and a wry grin. "Fer now I s'pose we should make sure she do come back around though"

Medicine check: 23

You patch up her legs the best you can and try to treat her head wound. You believe she should recover eventually. You hope...

 Ro detaches herself from the elf's face and turns around to see Twiglet holding a sword and covered in blood. She runs over and starts frantically checking him over. When she realizes it's not his blood she sheepishly signs [I thought you was bleeding to death maybe. ] and pantomimes extreme relief, wiping the back of one hand across her forehead. It leaves a smear of elf blood which she's too hopped up on adrenaline to notice.

She goes to hug Twiglet but then remembers that the elf is probably bleeding to death behind her. Turning around, she pulls out a healer's kit to stabilize the elf.

With Ro's help Tallanvor searches the elf and surrounding area for a key.

Perception roll: 25

Humblodt rummages in his pack. "Good thing I stocked up on sacks", he says cheerfully with a meaningful nod at the recumbent elf.