Rohuzar nods and looks to the others, gesturing onwards. 

Resuming your march through the wet forest, you continue along the lion's trail with Zip leading the way.  

It is not long before Zip returns to ground level, blinking that the trail has ended.  Ahead of you looms a large boulder, 15 feet high.  The ground on either side rises up to it like a small cliff in the middle of the wood.  While Grugga decodes the blinking message Zip is trying to deliver, a loud ‘Kee-harr!’ echoes.  A strange, navy-blue monstrosity strides to the edge of the boulder above you.  It cries out in fury and prepares to leap down to attack.

A Displacer Beast!  

INITIATIVE

• Displacer Beast  17
• Rohuzar  9
• Guilim  15
• Leelan  12
• Grugga  10
• Aubrey  9

(Note: Any attacks made against the Displacer Beast are at disadvantage unless/until an attack hits.  Once an attack hits, this feature is disrupted until the end of the Displacer Beast's next turn.)

The blue lion strikes first!  In one great bound it leaps from its perch, landing within 10 feet of both Rohuzar and Guilim.  The two long tentacles on its back lash out in attack!

Against Guilim:  Attack: 21 Damage: 5 bludgeoning and another 3 piercing.

Against Rohuzar:  Attack: 22 Damage: 7 bludgeoning and another 4 piercing.

After its attack it backs away, growling savagely.  It never gets within 5 ft so no AoO for Rohuzar, but due to Guilim's longer reach with his pole weapon, he gets an AoO as it leaves his range.

(AoO for Guilim and then all five of you are up!  Order of attacks is important!)

Attack of Opportunity: Attack: 19 Damage: 14

Disadvantage: Attack: 23 Damage: 7

Assuming the group decides to fight - Grugga orders Zip 15 feet up at his current position, and sets him to attack mode, targeting the blue lion. Then, Grugga moves 6 tiles to the bottom left of the blue lion within melee range and melee attacks.

Rolling at disadvantage in case he hasn't been hit before my turn.
Grugga:
Attack: 9
Damage: 9

Zip:
Attack: 6
Damage: 4

If we don't fight the lion, Grugga will follow the plan to the best of his ability.

Guilim reacts to the evasive catlike monster with a slash from his halberd.  To his eye, it looks like he just missed... but he feels the halberd strike something.  And just like that, the Displacer Beast snaps into clearer focus. 

(The creature's natural displacement defenses have been disabled - for the moment.  Attacks are no longer at disadvantage until the end of the creature's next turn.  Since disadvantage could have been rolled on the first attack roll, I will let you use the original damage roll.)

Guilim will move to follow after the creature, keeping his weapon out and in front of himself so he can stay back while striking. As he gets close he will plant his feet to steady himself and slash at the beast.

Attack: 8 Damage: 5

If his hit strikes he will call out to the spirits of his ancestors, his blade glowing with divine light as he Smites the Displacer beast.

Smite: 8

Rohuzar moves in to hurt the creature with an axe bite to the chest if he can

Attack: 26 Damage: 9 

Aubrey uses the powers of his talisman to blast the blue lion with a beam of golden crackling force.
Eldritch blast: 24 Damage: 4

Leelan quickly releases an arrow aiming at the "blue lion".

Attack: 14 Damage: 6

The Displacer Beast whips its tentacles furiously and snarls and snaps at the attackers surrounding it.  All of the attacks, but for Grugga and Zip, strike home and the monster seems to be seriously wounded.

The little armored halfling has hurt it badly.  It lashes out at him with both tentacles.

Attack on Guilim:  Attack: 22 Damage: 6 bludgeoning and 4 piercing.

Attack on Guilim:  Attack: 23 Damage: 10 bludgeoning and 5 piercing.

It then leaps over top of Guilim and races toward a small cave opening in the hillside. 

(In its flight, it draws AoO from Grugga, Guilim and Rohuzar.  If any of these attacks land, the displacement effect is disrupted for another round.  If none of them land, the displacement effect is re-established and all attacks are at disadvantage until one of them lands.)

Rohuzar AoO as he backhands with the axe

Attack: 10 Damage: 12 

Grugga will take the AoO:
Attack: 13
Damage: 4

On his turn, if it's still alive, he will dash to block the beast's path and order zip to shoot.
Zip attack: 10
Zip damage: 5

Guilim whips around as it jumps over him, attempting to strike as it lands near him.

Attack: 12 Damage: 9

Of the three surrounding the monster, only Grugga is able to strike a glancing blow as it leaps and darts toward the cave.  The others swing but the Displacer Beast contorts and dodges away from their blades.

Still, it is enough and Grugga’s attack again disrupts the creatures displacement defenses and it is subject to attacks without penalty.

(Everyone is up)

Aubrey again uses the powers of his talisman to blast the blue lion with a beam of golden crackling force. 
Eldritch blast: 11 Damage: 9
He then moves in behind the others. (6 hexes to the northwest.)

Rohuzar keeps charging after the displacer beast, and swinging his axe

Attack: 23 Damage: 10 

Leelan shifts to the side to get a clear shot and fires an arrow at the creature.

Attack: 25 Damage: 7

Leelan and Aubrey’s ranged attacks miss, with Leelan’s arrow narrowly missing Grugga as he sprints to cut off the monsters retreat.  Rohuzar’s aim is true and he cuts another deep wound in the Displacer Beast.  Likewise, Zip zaps the beast from above.  It is breathing heavily now and looks seriously wounded.

(Guilim still has his attack for this last round pending if he wants to join Rohuzar in pursuit.  It would take a critical to have a chance at a kill so I will proceed with the next round for now…)

Grugga manages to see the monster is making for the cave and he successfully sprints to put himself in position to block it.

Grugga:

 Bleeding a frothing, light blue blood from a half dozen wounds, the Displacer Beast screeches with beastial fury at Grugga as he stands between it and its den.  With all the might it still possesses it lashes out at him with its tentacles.

Attack: 7 Damage: 5 bludgeoning plus 3 piercing.

Attack: 26 Damage: 8 bludgeoning plus 5 piercing.

It then limps toward the cave around Grugga, incurring another AoO from Rohuzar and Grugga (and Guilim if he followed last turn).

Rohuzar’s AoO Attack: 23 Damage: 6