Meanwhile, in the Westwoods...

Quentin could probably hit either all three of the vine blights or the tree and VB 1 and 2.  You may want to remember that Mindartis is next to the tree, and some of the owls are being held by the blights.  The owls can probably be considered disposable, of course, since they are fey spirits temporarily in the shape of owls.

VB INT save: 9

Quentin aims at the three vine blights and suddenly an intense gravity pushes all the blights and owls there, trying to shove them all 15 feet away.

Con ST 14 half damage on successes and isn't pushed away: 27

Vine Blight con saves:

1 21

2 12

3 17

Vine Blight one stands in shock with half its leaves and bark blown away...blights 2 and 3 pretty much disintegrate, and so do the two grappled owls.

Prince Lintelér dismounts from his owl and attacks the tree: green flames burst from his longsword as he swings...  Attack: 8 Damage: 10 ...if he hits, a burst of flame scorches Vine Blight 1 for 4 damage.

Raven and Elwin still have attacks to make.

Re post 2382: Do the recently dismounted owls get to attack? 2 & 3 are gone, 1 already attacked. I don't know if Q dismounted or if he cast from the sky which would be totally boss. D should have done that. 

Any that have movement left to do so fly by the tree and try to open the tear M started

D Claw 20 if hit damage is 8 if hit damage is 10 if hit damage is 8 if hit damage is 12

Repost - I rolled 4 owls worth, and it shows as such in my posts record, but only see 1 on the thread. Maybe because I used line breaks not enters to save space? Anyway, if those rolls are gone here are new ones

L Claw 15 if hit damage is 4

M Claw 11 if hit damage is 8

R Claw 5 if hit damage is 8

Yeah, I will count any dismounted owls as able to attack: being dismounted would only have used some of their movement, and giant owls have a lot of movement. 

Quentin did not say he dismounted, I am counting him as still airborne, but Owl L is available, because the prince got off to do some pruning with his sword.

I don't understand what you've done there with the damage of Owl D, though... Okay I see...original post only shows 4 damage rolls, one owl attack. XD We will hold Owl R's attack in reserve until we know what Raven is doing. Owl M and D hit.

((it was 4 separate attack rolls on separate lines, but the forum telescoped them down to one attack and 4 damages. Only count the first, and see re-rolls on post 2389))

MOVE: Fly toward tree
BONUS: Use Hexblade's Curse on tree - crits on 19/20, +3 bonus damage
ACTION: Two attacks toward tree -
  Attack - 19, Damage incl. crit - 13
  Attack - 25, Damage incl. crit - 9

Elwin swooped down toward the tree, struggling to maintain a streamlined form as he did. He muttered a curse as he closed, then quickly did a double-strike at the enemy with his spear. Pivoting in mid-air, he returned to his defensive stance.

Raven dismounts and attacks any that are between ehr and the arch.

To hit: 21

Damage: 13

Sneak attack: 10

Okay, Raven's owl gets in a quick attack as well.

With a creaking roar of rage, the tree attacks!  (Deciding who: two air attacks, two ground attacks...1  2  5  2 5)

One mighty branch swings through the air, smacking at an owl... Attack: 15 Damage: 17

Another takes a whack at Elwin...Attack: 15 Damage: 16

Powerful branches erupt from the earth to snatch at Mindartis and Raven!

At Mindartis: Attack: 10 Damage: 10 " If hit, you are grapples and take 11 points of damage at the beginning of each turn till the grapple is ended: can be escaped either by DC15 strength check or 6 points slashing damage to the root (which is not subtracted from the overall health of the tree.)

At Raven: Attack: 26 Damage: 12 " If hit, you are grapples and take 12 points of damage at the beginning of each turn till the grapple is ended: can be escaped either by DC15 strength check or 6 points slashing damage to the root (which is not subtracted from the overall health of the tree.)

The one surviving vine blight also takes a whack at Raven: Attack: 15 Damage: 9 and if hit (and if Raven is not already grappled by the tree) grapples, DC12 strength check to escape as an action.

Sooo, Mindartis takes 12 points damage and is caught in a deadly grapple by the tree Blight.

The tree misses Elwin, the owl and Raven, but Raven is hit for 12 and grappled by the Vine Blight, and is restrained .

The party is up!

((What kind of damage? Or did you chop it in half already?))

Bludgeoning damage...I did not cut it in half...and I made a mistake, it looks like you are grappled but do not take that actual damage until the beginning of your turn.

((the roll for owl R was 16 to hit, 8 damage on the tree ))

Del yells instructions while concentrating on the owls, playing loudly on Ziia: Skreeee - b-d-d-d-d-djeeoowwmmmm...baaahm---bahm-bahm-baaahhmm..., the owls claw at the plants, rather than flying by they stick around to harry their targets

1 & D on the vine, rest on the tree

1: Claw at VB1 11 if hit damage is 10

D: Claw at VB1 20 if hit damage is 13

L: Claw at Tree 6 if hit damage is 10

M: Claw at Tree 6 if hit damage is 7

Q: Claw at Tree 20 if hit damage is 4

R: Claw at Tree 9 if hit damage is 8

When his turn comes, Dell, maintaining concentration on the owls, sends an extra Ya ain't kindlin' at the tree [Tooltip Not Found] DC15 INT save or 5 psychic and subtract 2 from its next save 

Raven strikes at the tree.

to hit: 21

Damage: 10

Sneak attack: 10

Bonus Action: Fey Step
Each creature of my choice within 5 feet of me takes 3 Fire Damage. (I select any hostile creatures within 5 feet of me to take that fire damage)

Action: Reckless Attack
Greatsword (reckless) Attack 1: 25 Damage: 13
Greatsword (reckless) Attack 2: 22 Damage: 15

All attack against Mindartis are made with advantage

Mindartis, still growling, closes his eyes and imagines stepping away from the tree grappling it. Free of the tree's grasp, and turns around and rushes back towards the tree, aiming to try and slices at it again.

Owl D finishes off the Vine Blight! (Yeah, I've already added in Owl R's damage. Wow, I was kind of scared at throwing a Challenge 7 monster plus extras at you, but you guys are making salad out of 'em.)

((Rage is a great thing... plus have 8 extra owls helps too))

Oh, tree INT save: 17

Quentin and Elwin have attacks yet...

Prince Lintelier takes another swing with his longsword: Attack: 14 Damage: 10

A large pile of sawdust is accumulating around the roots....this tree is probably going down pretty soon.

ACTION- Two attacks on the tree -
  Attack - 13, Damage incl. crit - 8
  Attack - 12, Damage incl. crit - 11
BONUS- Extra attack from Polearm Master -
  Attack - 18, Damage incl. crit - 11

"Fall!"

With a roar, Elwin continued spinning, weaving, and thrusting with his spear to attack his enemy. His final flourish spun his weapon to strike with the backside, after which he rotated quickly to come back to face the tree, his spear resting on top of his shield, pointing at the creature.