Rixton:

An arrow pierces my left bicep. I grimace and snap the shaft off quickly. I eye the shaman, searching for an opening as I toss the shaft aside. Twirling my blade, I jog forward, feinting one direction, then another to draw a tell from the shaman. When I am close and confident in my read on him, I strike.

Bonus action: Insightful fighting (Insight = 14)

Short sword (+1) Attack: 13 Damage: 8

If Rixton's insight check is higher than the shaman's deception roll, sneak attack damage = 6

Deception (for shaman): 19

Rixton's blade finds its target, but the damage done is much less than what the rogue had hoped for. 

Andor 

After blasting one of a pair of barbarians coming out of the magical fog Andor spurs his horse down the hill toward the two wildmen. As he moves to ten feet away from them he feels the storm rage inside him, almost tearing out of his throat, knowing what to do next he roars out a cone of lightning hitting both of the enemy before pulling hard on the reins and charging back up the hill as far as he can go.

Movement to F6

Bonus action Casts Dragon's Breath choosing lightning as damage type for 10 unless a DC 14 Dex save halves it.

Movement to C7

Ladrian

Moving his horse to F16, he stops and aims his crossbow at the shaman

Attack: 26 Damage: 14

He then quickly shouts at Rixton: "Let's go! Let's end these two quickly, so we don't get separated from the rest of the party!"

Carrow

Stepping forward he engages the Uthgardt (8) emerging from the fog with a savage overhead strike. 

Attack: 7

Damage 9

Slayers Prey: 5

Ensnaring Strike: Strength 11  Damage if failed 6

Dexterity saving throws: Barbarian 15: 7 | Barbarian 17: 4

Andor exhales a magical blast of lightning that strikes both barbarians. When the flash of light and crackling noise subsides, only one barbarian (17) remains standing. The other has fallen lifeless in the snow. 

(Vigan's action is next, to be followed by all barbarians and the shaman)

Vigan

The goliath attempts to dodge the wild swings of the greataxe, but suffers a minor gash in his arm as its blade connects.  Vigan quickly counterattacks before the Uthgardt can enjoy his success, sweeping low with the blade and then using his momentum to aim the butt of his glaive at the barbarian's face (#8).

Attack (advantage): 17

Damage: 8

Bonus Attack (advantage): 25

Damage: 9

The last two barbarians make their way out of the fog, but one of them (16) is too far to the east to engage in the melee. The other (14), however, surprises himself by suddenly coming face to face with Carrow. He makes a quick stab at the ranger with his spear...

• Melee spear attack: 22 | Piercing damage: 7

The barbarian (17)  to the north, seriously wounded by Andor's lightning attack, retreats into the fog. Fighting through the two wounds he just received from Vigan, barbarian 8 takes another swing at the goliath with his greataxe...

• Greataxe attack (w/ advantage): 20 | Slashing damage: 14

Barbarian 3, seeing the severity of his shaman's wounds, hurls his spear at Rixton...

• Ranged spear attack: 16 | Piercing damage: 4

And the shaman, bleeding badly, takes a few steps backwards; as he does so, Rixton hears the shaman's voice as it utters the words to some sort of incantation. The moment his voice falls silent, fiendish apparitions begin to swirl around the shaman. Rixton, although unfrightened by the appearance of the specters, feels his life and energy being drained. (11 necrotic damage, which can be halved on a successful DC 12 wisdom saving throw). 

(All players may act, in any order)

Updated map: 

Rixton:

A spear grazes my cheek, causing copious blood to flow from the wound. While glancing to the side, I feel my breath stolen from me by a painful drain on my energy.

WIS save: 14

The attack is unexpected and I cannot resist magic drawing the life out of me.

I take a deep breath, steeling myself, and slash at the shaman, perhaps a little impulsively.

Short sword (+1) Attack: 9 Damage: 8

Turning, I throw my dagger into the bushes at the barbarian hiding there.

Bonus action dagger Attack: 14 Damage: 2

 Vigan

The Uthgardt strikes Vigan with a mighty blow from his weapon, but the goliath stands firm.  Shaking the hit off, he growls and raises his glaive as if to slice at the barbarian, only to strike him with the blunt end, before bringing the blade down on him.

Stone's Endurance (reaction): 10 - no damage taken from last attack.

Bonus Attack: 13

Damage: 8

Attack: 9

Damage: Damage: 14

After wounding the shaman, Rixton spins and hurls a dagger that sticks soundly into the chest of the barbarian lurking in the bushes. The barbarian staggers to his left and then collapses face down.

Vigan stands toe to toe with the axe-wielding barbarian, landing two heavy blows with his glaive. With wild eyes and a growl in his throat, the barbarian holds his ground and prepares to retaliate.

(Actions for Carrow, Ladrian, and Andor are next)

 Andor 

As the fight between his friends and the barbarians continues on the edge of the fog Andor guides his mount down the slope towards the action (G6) unleashing another blast of lightning which tears through the two barbarians and the fog cloud possibly catching the other enemy who fled back inside after being wounded.

Breath attack 9 lightning damage (round 2/10) or half if saved against DC14 Dex

Dexterity saving throws: Barbarian 14: 2 | Barbarian 8: 13

Once again, Andor strikes two barbarians with a blast of lightning. After being bathed momentarily in crackling white light, both warriors stand ready, committed to continuing the melee.

(Ladrian and Carrow to act next)

Ladrian

He pulls his xbow again at the shaman and shoots

Attack: 16 Damage: 3

Forgot to add my bonus dmg: it's +4

Carrow 

His last attack not finding its mark he leans back preparing for another strike his weapons raised again he tries to find his mark in the swirling melee of the two furious combatants to his front. Catching movement he spins on the balls of his feet to be met with another foe (14) before the barbarian leaves the fog the ranger lunges at his new prey.

Attack 16

Damage 4 

Ensnaring strike. Str 11 3 

Ladrian's shot ends the shaman's life. As the tribal holy man collapses, the spirit guardians that he summoned  fade into nothingness.

The life and strength that remains

in the barbarian (14) is too little for him withstand Carrow's attack. The barbarian slumps to the ground and breathes his last.

Barbarian (16) turns and charges Vigan, hoping to run the goliath through with his spear...

• Melee spear attack: 6 | Piercing damage: 3

Simultaneously, barbarian (8) yells something unintelligible in Bothii and takes another reckless swing at Vigan with his greataxe...

• Greataxe attack: 9 | Slashing damage: 5

The lone barbarian who escaped into the fog cloud is still nowhere to be seen.

(All players may take their next action in any order)

Updated map: 

Vigan

The goliath attempts to anticipate the next movements of the axe-wielding Uthgardt, while engaging a second barbarian running at him with a spear.  A quick feint and dodge results in the spear tip passing harmlessly to the side of the goliath's ribs, leaving the barbarian (#16) wielding it wide open to attack.

Attack (riposte): 27

Damage: 27

Focusing on the avoiding the spear leaves Vigan open for a successful slash from the greataxe across his back.  Grunting in pain as a wound is opened, he spins to face the Uthgardt (#8) and attacks twice in quick succession.

Attack: 13

Damage: 8

Bonus: 14

Damage: 9

OOC - Forgot to roll with advantage, will post second rolls for the last 2 attacks below.  Edit - didn't make a difference!

6 & 2

Carrow 

His attack finally finding its mark he quickly pivots again grabbing his sword with both hands the Ranger slashes at his original quary in an attempt to leave Vigan with just one foe. 

Attack 13

Advantage 8

Damage 9 

Crit Damage 2 

Rixton:

Seeing that the immediate area is clear of enemies, I examine my wounds and watch the battle wrap up to the north of me. I whistle for Irena to come, unsure if the training has taken yet.

Animal Handling: 22

I bend down to examine the shaman's body for anything notable.

The spear-wielding barbarian doesn't live long enough to regret his daring rush toward the goliath; Vigan cleaves the man in two with one swing of his glaive. A moment later, the axe-wielding barbarian falls under a barrage of steel, struck three times in quick succession, twice by Vigan and once by Carrow. 

Somewhere in the fog lurks the final barbarian...