Ben:

Managing to remain free of the vines for now, Ben moves over to the location where the invisible assassin is displacing the vines.  He stabs at the invisible creature with his magical dagger, hoping to score a hit and further trap him.

Attack with disadvantage:   Attack: 12 Damage: 6

On hit, Ensnaring Strike activates 

Wisdom Saves: 4 and 12

Titaani is going to rush forward to where Ben is, but skids to a stop when she sees the vines. She stays at the edge of the clearing. "Don't worry Tiny! I'll get you out of there!" 

Hearing his master's voice, Tiny continues to struggle: 14

Ben calls out in Sylvan as he manages to evade the expanding patch of snaking vines. He swings at the invisible assassin, but catches air where he thought the wily orc was captured.

Tiny manages to break free of the vines.

The owlbear is driven into a panicked frenzy trying to escape the grasping greenery once again. Strength save: 20

Matilda, still restrained and now clutching her head, may act. (DMed)

(Just some more rolls: 19, 11)

--------

Horatio:

"Hey! This is going to sound crazy, but my friends were talking to a real unicorn when someone attacked it. My friends chased the attacker off but they all ran inland. Can you save my friends? I'm trying to get to them but this is a long swim and that attacker could be real dangerous!"

He sees the old centaur contemplate his words as Horatio continues to rush through the peaceful waters toward the lake shore.

"It's too late," calls back the centaur. "This realm is fading."

--------
√ Tiny (near assassin, freed)
   Matilda (near assassin, restrained)
 √ Titaani (at edge of clearing)
 √ Owlbear: (near assassin, trying to break free)
√ Ben: (at clearing, speaking with denizens of clearing)
√ Horatio: (still swimming... talking to a centaur...)
   Centaur
   Tree? Goats? Squirrels?
   Lamorna: (vanished)
   Assassin (invisible, restrained again)

The owlbear remans trapped.

You can tell from the disturbance in the vines that the assassin continues to struggle. DC12 Strength save: 8

A tiny unseen voice calls back to Ben from the tree in Sylvan, "Yes, we can sense that the invisible one is a troublemaker." Three tiny figures – pixies, you recognize – appear on a branch. "We've had enough trouble for one day. Be careful around those goats."

Matilda is up next.

Matilda yelled out to whoever was in her head that the invisible man was a f***ing b*****d who needed to die for attacking the unicorn.

She waved about with her dagger with very little chance of success...

Attack: 15 Damage: 6

Exasperated, Horatio replies, "The realm? Yeah, this place sucks! So many powerful people doing nothing while a handful go around doing great evil. How about you not be one of the lazy folks who just roll over and continue to let it all happen? You can start by trouncing an assassin and saving my friends!" 

Matilda manages to slash the assassin. You hear him gasp and squirm and curse.

You can hear the pixies speaking to each other quietly. (Something about "goats" in Sylvan.)

Matilda: Make three DC12 Wisdom saves or become a goat.
Owlbear: 9, 12
Assassin: 18, 12, 16.

More pixies begin to pop into vision, their little butterfly wings fluttering. "Please stop," they implore quietly.

The owlbear becomes a goat.

The assassin tries to break free once again: DC 12 STR check: 13

-----

"I wish I could help," says the centaur to Horatio, still frantically swimming to the edge of the lake. "I am old and weak and my vision is poor. Tell me what I can do. But I think you should return to your own world before Prismeer disappears entirely."

The assassin breaks free and manages to scramble away, somewhere near the edge of the clearing, still invisible.

The owlbear goat bleats passively.

Everyone may act.

Wisdom Saves: 6  and 16  and  18

Ben:

Replying in Sylvan, Ben says, "As you wish, I will stand down out of respect for your domain, though I greatly desire to ensure no assassins remain to make more attempts on the unicorn's life.  If you would be so kind as to return my companions to their normal forms, I am sure I can convince them to stand down as well--or at least continue the chase away from your glen here."

Ben sheathes his weapon and walks over to Matildagoat, patting her head reassuringly.  To the pixies, he bows and says, "Out of respect for my Oath to the Ancient Ones, I defer to your preferences in your grove."

Oblivious to Ben's discussion with the fey, Tiny, breaking free from the vines, leaps forward furiously at the assassin. Titaani mutters something angrily under her breath and Tiny lashes out at the attacker with glowing purple paws.

To hit: 20 Damage: 1 If this hits, the assassin must make a con save please. 

Continuing to swim in a full panic, Horatio let's the Centaur's words sink in. "We can't." He finally replies. "We've all lost things, and I think we could live without them and just go... but one of us... her brother was taken. Another cat-squid lady we met, her baby was taken too. We can't just leave them to those Hags. We have to try to get them back. If we have to kill every Hag and Hag-lover in Prismeer to do it then so be it!" He is himself shocked by his own vitriol. I was a boy without a family too. He thinks to himself. What was I doing with my life anyways? Did I ever even have dreams? Goals? What good is crying about losing a life so aimless when I could save children?.. Even if I die trying?

Matilda polymorphs into a goat. She struggles for a moment, and then begins to nibble at the abundant foliage.

Tiny, torn free of the vines, and ignoring both Ben and the pixies, lunges for the invisible assassin and manages to catch him with a rake of savage bunny claws. DC 10 CON Save: 5

The assassin pops into view. "Off me, you filthy overgrown rat!"   He pulls his two daggers out and tries to sink them into Tiny:

Dagger Attack #1 vs Tiny: 13. Hit: 10 piercing damage.
Dagger Attack #2 vs Tiny: 17. Hit: 10 piercing damage.

He then disengages and runs into the brush.

The pixies respond with a wave of fey arcana:
Tiny DC12 Wisdom checks (presuming he's still up): 9,  16,  19.
Assassin Wisdom checks: 14,  8,  19, and  11.
"Please, please!" they cry, and more pixies appear. There must be well over a dozen visible now, on the boughs of the dying old tree or inside the little twig houses.

Tiny vanishes into whatever pocket dimension he calls home. 

The assassin, now visible, polymorphs into a chicken. It proceeds to run around for a moment and then pecks at a spot on the ground.

"First those red-hatted lunatics tried to stone us," cries one of the pixies to Ben. "And now this! The one called Zarak tries to ambush the unicorn to chop off her horn, and then you all try to chop down Zarak! The fighting must stop. Your friend Matilda will be fine. We're so sorry for the inconvenience."

Matilda, with a current Intelligence of 2, understands none of this, but does find a tasty root to chew.

Everyone may act.

----
Meanwhile:

Continuing to swim in a full panic, Horatio let's the Centaur's words sink in. "We can't." He finally replies. "We've all lost things, and I think we could live without them and just go... but one of us... her brother was taken. Another cat-squid lady we met, her baby was taken too. We can't just leave them to those Hags. We have to try to get them back. If we have to kill every Hag and Hag-lover in Prismeer to do it then so be it!" He is himself shocked by his own vitriol. I was a boy without a family too. He thinks to himself. What was I doing with my life anyways? Did I ever even have dreams? Goals? What good is crying about losing a life so aimless when I could save children?.. Even if I die trying?

Horatio finally makes it to the edge of the shore (but is still prone in the shallow water.)

The old centaur nods and sighs. "The other members of my clan galloped away to safety before the mists enveloped Prismeer, but I was too old to keep up with them. I don't pretend to know the causes of this realm’s impending destruction, but I expect the hags are at the heart of it. I can give you directions to Loomlurch if that’s where you aim to go. That's where at least one of them - Skabatha Nightshade - can be found. I don't know that I can help you more than that."

Titaani lets out a shriek as Tiny travels back to Titania's pocket of the Feywild. She then lets out another, silent shriek as Matilda turns into a goat.

"Oh no!!" She whispers, running to Matilda. "Matilda! Matilda can you understand me? Please tell me you're still in there..."

She starts to softly sob, the insane events of the day too much for her. 

Ben:

Already beside Matildagoat, Ben puts his arm gently around Titaani and says, "The pixies are just protecting their glen.  I have been speaking to them and I think we are safe if we take no hostile action.  They have already said Matilda will be okay."

Speaking in Sylvan, Ben addresses the pixies, asking, "What can we do to protect the unicorn of the Wayward Pool?  And defeat the hags to restore Zybilna to her rightful place?"