(Ah yes, sadly. :( )

Uncaring of what the others say, Mercy sneaks into the brush to tail the gnolls. She draws just one of her curved short swords as she creeps around their rear flank.

Stealth: 18

(In case things go really badly) Initiative: 5

(Do I see anything else worthy of note?)

Perception: 15

Everyone who hasn't - make stealth checks.

DK, I assume you are probably ahead or behind of Mercy?

Who else is going closer? Who is staying at a distance?

(I'll resolve Mercy's checks when I know these things.)

Dyoken moves up ahead (Stealth if you insist: 13)

Muireach is holding his Fey Step for as soon as Mercy or the group charges.

(I guess the question is - is anyone just charging this group? Cause if you are, you don't have to roll to stealth, but just be explicit with your intent! I assume Merrick is likely holding back. Vivi is going to do whatever the most of you seem to do.)

Dyoken moves off to the side and out into the open along the path (so as not to provide cover for his opponents) then charges.

Mercy ducks into the tall grass and approaches what seems now like scouts. Two of the kobolds seem well armed, while the third seems to be of lower rank. She hears a guttural growl as the large canine suddenly looks her way. Mercy stops in her tracks and holds her breath. She almost believes she locked eyes with the beast, but it turns its head away and continues to lead the gnolls away from her. There was something off about that dog... Smoke or steam blew from its nostrils...

DK barely manages to get around the group before the beast howls. As close as she is, Mercy sees this hound has a fiery maw completely with sharp teeth. It charges toward DK while the gnolls steady their bows.

It fight time.

Dyoken roars with fury, entering a Rage as he closes the distance, meeting the beast along the way. Dyoken Recklessly stabs at the dog, hitting 21 for 17 for his 'Sneak' Attack. If the beast still stands Dyoken will attempt to use it for cover.

(Attacks against Dyoken have Advantage. If an archer hits him...)

Turns out I can’t ready a bonus action, so I’ll just do that now.

Muireach steps into the bushes and steps out from hammerspace behind one of the gnolls near Dyoken, “Hello, poochie. Roll over.” Both undamaged gnolls need to make a Wisdom saving throw or be charmed by Muireach.

Muireach will Green-Flame Blade any gnolls that don’t bend the knee.

(Mercy me!)

(I believe Mercy is up before Muireach, so-)

She snakes in for an attack against one of the bow-wielding gnolls, attempting to slash his throat:

Attack: 24 Damage: 9

Luthok limps slowly in towards the other combatants keeping about two dozen feet between him and the enemy a skeletal hand appears and attacks any gnolls who don't become charmed. 

Chill Touch : Attack6 Damage: 6

Merrick follows Mercy into the brush (Stealth 12 precombat)

When the Gnoll howls, Merrick scoots out of the treeline, rapier in hand. He brings the blade along the side of one of the bow wielding archers, cutting with rakish audacity, before disappearing behind Dyoken's burly form in a blur of fancy footwork.

Merrick truly disappears, moving behind the big man's legs as if he were his shadow. (Stealth 28)

Dyoken throws caution to the wind as he charges the hellhound by circumventing around the group. 

Merrick ducks low avoiding the notice of the gnolls it would seem as he suddenly gashes one of the gnolls against the leg with a devastating attack before sliding under DK and disappearing behind the burly man. 

Muireach's poof causes the two bow gnolls to feel friendly to the elf and only the elf. They won't pose a threat to him at this juncture. Muireach stands behind the hellhound that is distracted by DK's wild approach and stabs into its flesh. It howls in pain as green flames hop over from Muireach's blade to the nearby, non-bow gnoll.

Mercy sees one of the gnolls already bloodied by Merrick's slash n' dash and decides to try for its throat. She fumbles, slicing the gnoll's back, as the other bow-wielding gnoll's neck comes into view. She spots a necklace with teeth, but she spots at it's lowest point a crude emblem signifying that he is more powerful than she previously estimated. 

The gnoll that stands adjacent to the hound brandishes a spear and pokes twice at Dyoken!

(Attack on Dyoken - Attack: 9 Damage: 7 & Attack 2: 6 Damage 2: 4)

The powerful gnoll aims at DK with its longbow, then commands in gnoll, (spoiler for those who speak gnoll)

(Attack on Dyoken - Attack: 17 Damage: 6, Attack 2: 8 Damage 2: 10)

The gnoll which just poked at DK pokes again!

(Attack on Dyoken - Attack: 23 Damage: 9)

The other bow-wielding gnoll aims at DK and launches two arrows in his direction.

(Attack on Dyoken - Attack: 16 Damage: 4, Attack 2: 6 Damage 2: 10, and if either hits, - 10 movement until the end of your next.)

(Part two inc. Checking something.)

 (Edit: dice might say manipulated cause I forgot someone's second attack oop)

Vivi seems worried at first that everyone seems to be gunning for her barbarian friend, but he seems remarkably unscathed! She instead runs up to the bow-wielding gnoll and issues her attack! ... It misses.

DK wildly attacks the hound, leaving gushing wounds wherever his blade struck. The hound attempts to repay the human in kind! Merrick and Dyoken see the creature's mouth open wide as wild, red fire pours from its mouth toward the both of you!

(Merrick and DK, make DEX saves vs DC 12 or take 22 fire damage. If you succeed, you take half as much rounded up.)

Luthok tries to get his skeletal hand to attack the spear-wielding gnoll, but it seems to have no effect!!

Enemies 

Hound (Taken -33) [H]
Spear Gnoll (Taken -6) [SG]
Bow Gnoll (Taken -24) [BG]
Powerful Gnoll (Taken -0) [PG]

Initiative

Merrick [Me]
Muireach [Mu]  
Mercy [Mc]
Gnolls 
Vivi [V]
DK [D]
Hellhound
Luthok [L]

Rough Map Sketch

[Me] [D] [H] [Mu]                    [PG]
             [SG]                         [BG] [Mc]                                         [L]
                                             [V]

Dyoken bats away the first arrow as it approaches, even as teeth, spears, and arrows strike all around. DK seems unfazed by the onslaught avoiding harm through a combination of luck, speed, and thick skin, but he surely can't withstand such an assault for long. He continues to make an obvious target.

Dyoken moves without thought to duck the flames (Danger Sense Dex: 16) He avoids the brunt of the flames, but he can't avoid them all, yet he seems hardly affected by those that do catch him.

He Throws a fist at the Spear Gnoll and tries to grab a hold of its matted mane, Recklessly hitting 18 for 7 bludgeoning. (On hit Athletics: 25) He sheathes his sword, and lifts the captured Gnoll off the ground, holding it up as a shield as he moves closer to the archers. (Ending just North of Muireach still in reach of the Hound if it survives.)

(Note: attacks against will have Advantage)

(On that note, am I correct in reading the above as: the attacks against, proceeded DK's Reckless Attack and so did not gain Advantage, but were yet Resisted through his Rage, due to his opening combat?)

Muireach will shout over to the charmed gnolls, “As you’re new king, stop attacking my subjects! Bad dogs!”

Muireach then returns his focus to the hellhound, “And now for you, hotdog.”

Muireach brings Calibolg along the beast’s side in a streak as he pulls the flame from the dog in an arc, striking the beast: Attack: 25 Damage: 11 magic slashing and hurls the hellhound’s flame toward the gnoll facing Dyoken for 5 fire damage!

Oh also, if we deal any damage to them, the charm stops... so... 

Merrick ducks to avoid the fiery breath, but even so, is badly burned. He clamps his teeth to avoid screaming in pain as red welts form all over his arms. He hops out from behind Dyoken, cutting the distracted hound with his rapier before running to the safety of the woods. (OOC no opportunity attack from hound due to fancy footwork). He ducks behind a tree, his back pressed flat against the trunk (Stealth 20)

Merrick is no coward, but one more burn like that and Nana would be crying at his funeral. And that just wouldn't do.