Gash casts fire bolt at the githyanki that sneaked up behind dog.

Fire bolt Attack: 14 Damage: 2 + 6 (rolled separately in case there are any 1s rolled)

G1 swings his great sword at the Bulwark.

Greatsword Attack: 21 Damage: 10

The monstrosity attacks (3) Dog and (2) Dog. The strike delivers that lands delivers an extra 11 in psychic damage from the creature's tangible manifestation of rage pouring through its attack.

Hook Attack: 18 Damage: 15

Hook Attack: 16 Damage: 14

(Martin, Dog, and Bulwark are up!)

Dog receives 18+14 damage and Bulwark receives 21 damage. The fire bolt misses the githyanki.

Martin will shoot twice at the Gith with a hordebreaker shot going at the monstrosity

Attack: 26 Damage: 11
Attack: 21 Damage: 10

Attack: 14 Damage: 14

Martin's first shot is too high but his second finds its mark. Critical hit roll: 92 It's too bad he's not holding any weapons, because you would have disarmed him.

Dog and Bulwark are up!

I forgot the zombie's slam attack against G2 as ordered by Gash for his bonus action.

Slam Attack: 7 Damage: 7

Dog casts shield in response to the attack, which just works to make it a miss.

He attacks again!

Attack: 24 Damage: 8 plus 3 fire damage and then an extra 12 to the gith

Bonus Attack: 25Damage: 9

Critical hit roll: 16

Dog's strike stuns the monstrosity for a brief moment, allowing him an opportunity to escape from the melee. (Free disengage on Dog's next turn.)

The fire from his first strike leaps to the githyanki, who screams as he immolates and falls to the ground, dead.

(Bulwark is up!)

Bulwark deems the gith beyond words, and ignores them for now, again laying into the monstrosity with two reckless swings.

Attack: 17 Damage: 14

Attack: 28 Damage: 21

The first strike thuds against the creature to no effect but the second cracks bone beneath the tough skin and muscle.

G2 swings at the zombie again.

Greatsword Attack: 17 Damage: 18

The zombie is cut almost in half by the githyanki, who then runs over to Gash.

G3 swings at Dog twice.

Attack: 18 Damage: 15

Attack: 16 Damage: 17

G2 swings at Gash.

Attack: 14 Damage: 25

(Bah. I wasn't using their multiattacks before. Tock, Gash, and Althus are up!)

Tock does what Tock does - hide behind the tree (stealth check 26) and shoot the monstrosity:

Attack: 26 Damage: 16

Althus continues trying to beat down the monstrosity with his sword.

Attack: 16 Damage: 9

Attack: 17 Damage: 11

Gash uses Nimble Escape as his bonus action to disengage from G2 and steps back 30ft. Then he casts Hold Person on G2.

Wis Save DC: 16

G2 WIS(16) save:  11 - G2 is paralyzed

The monstrosity is breathing raggedly but its rage is unabated. It slashes at (2) Dog and (1) Dog with its (probably) final burst of fury. (The first successful strike adds 16 psychic damage.)

Hook Attack: 18 Damage: 20

Hook Attack: 18 Damage: 20

Dog takes a brutal hit but the second one misses. The creature's anger courses through his mind, wracking him with psychic pain.

(Dog, Martin, and Bulwark are up!)

Dog uses he reaction again to cast shield and the monstrosity's first hit gets shunted again to the side (unless I'm messing up turns and reactions?)

(Nope. Damn Dog is hard to hit!)

As the monstrosity lays into Dog's magical shield, Bulwark lays into its ungaurded side. Reckless.

Attack: 24 Damage: 13

Attack: 18 Damage: 15

Martin looks at the paralyzed gith and takes a moment to aim for its neck (sharpshooter shots)

Attack: 20 Damage: 25
Attack: 21 Damage: 18

Critical hit roll: 97

Bulwark fells the monstrosity, which hits the ground with a leathery thud. Martin's arrow pierces the githyanki in the neck. His eyes go wide and he drops his sword. But he is still breathing and standing. (G2 is disarmed)

(Dog is up!)

Dog takes two hammer swipes, non-lethally, with one last try to talk. "Answers. What's her plan. Now."

 Attack: 24 Damage: 14
 Extra Attack: 25 Damage: 11

(Also is there a healing spell Dog was supposed to benefit from?)