Kadevii runs down the tunnel. "Praxius!"

(Dashing to make it next to him)

Quiggley brings up the rear dashing 60 feet in flight.

Theo stays near the back of the group, prepared to draw his guns if needed.

Praxius, gritting your teeth and visibly seeing the wave of magical energy coming towards you. You steel your mind and feel the creep of a dominating presence linger, yet through sheer will you force the presence from your mind and stare down at the figure who had attempted to dominate you. Just as Kadevii lands beside you. Nyka lurks within the shadows not far from the pair of you, The three of you stare down the tunnel at this individual. 

Lowering their hand to their side, this individual stares back up at you. Un moving and unflinching, while you are unable to visibly see their face due to the dark interior of the mine and a hood covering their head, you can all but feel their smile. Without a word, They wave their hand again. 

Praxius, Still feeling the burn within your eyes you can see an aura of arcane energy float around the individual. They vanish from sight, yet for the time remaining you can see the individual cloaked in arcane energy dash further down the incline and deeper into the mine. 

Strider rushes out after the lot of you, drawing his longsword from his side once more. "Whats happening?"

Shaking off the dominating press against his mind, Praxius snarls, "They are trying to get inside my head".

He then moves after the figure, disappearing after 35 feet and re-appearing right next to it, Frostbrand already arcing towards the magical energy emanating from it's head.

Then with bulging muscles he reverses the motion of the sword mid swng to bring it back across the chest area of the person.

Movement: 35 feet towards creature
Bonus Action: Fey Step right behind them, blocking the tunnel
Action: Attack
1 - Great Sword with Advantage (for reckless attack), using Great Weapon Master (-5 to hit, +10 Damage): (10,7)+8-5=13, Damage: 2+5+5+10=22 [magical slashing] + 6 [cold damage]
2 - Great Sword with Advantage (for reckless attack), using Great Weapon Master (-5 to hit, +10 Damage): (5,13)+8-5=16, Damage: 6+3+5+10 = 24 [magical slashing] + 3 [cold damage]
Special: Slasher - On hit reduce target speed by 10 feet, Reckless Attack - Attack rolls against you have advantage until your next turn.

Paca continues forward towards Praxius and the 'enemy' while shouting back to Strider, "Oh more trouble, hope you know how to handle yourself if your coming with, that would at least make one of us who can" Paca jests as he jaunts along. Paca also casts Blade Ward on himself as he approaches the others

Kadevii rushes forward as the man begins to retreat. “Hold it! You’re not going anywhere!” he calls out, casting entangle, DC 16 STR save

Quiggley flies 30 feet forward down the tunnel before witnessing events seeing the opponent trying to hide themselves and flee, Quiggley uses his sorcerous power (1 sorcery point, extend doubling the range) to cast Faerie Fire on the area of a 20 foot cube, covering the opponent in a purple fire that reveals it.

Dec save 15 for Faerie Fire.

Nyka sticks to the shadows and starts to head down the tunnel if able. To Praxius {Where are they!}
If the creature becomes visible, he'll fire with his shortbow. 

Sneak Attack with Shortbow: 20 to hit, 4+5+8 = 17 Piercing. 
Bonus Action to hide again: 30

Theo stays back while everyone else attacks and casts spells. “So, who are you, and what are you doing here?” Theo asks. “You’ve tried to cast a spell on my friend, and then run off. What is your purpose in here? Are you trying to kill us? Who are you working for?”

Persuasion: 22

The figure lurches in place, clearly startled by the sudden appearence of a Massive individual swinging a devastating looking blade towards them. However they prove to be quicker on their feet than Praxius had thought. Deftly Dodging both strikes made towards them, their movements while to an untrained eye may appear to be sloppy and uncoordinated. Praxius however can tell that they have decades of experience in battles, wasting no movement and only dodging the necessary amount to ensure they are not struck. 

However due to their focus on the large Barbarian, they are unable to move their foot in time enough to be unaffected by creeping vines that srping up from beneath the dirt. Cursing under their breath in an unfamiliar tongue to you Praxius, Seemingly knowing that something else is coming. They drop as low to the ground as they possibly can just as a wave of radiant, divine light jettisons from Quiggleys out stretched palm. Causing dancing fire flies to complete engulf the interior of the tunnel, making everything much easier to see for those who are unable to see i nthe darkness. However the figure is unaffected by it. 

Now panting for breath following the rapid assault, the figure regains their feet. 

Initiative 1+5= 6

Quiggley will wait for an opportunity to use Fire Bolt on the agile individual if the others don't stop him first. He is also ready to counter spell any spell the individual may try to cast.

Firebolt 14+7= 21 ; damage 13

Nyka moves quickly and silently. He positions himself and aims for the disturbance in the vines. He fires, then quickly moves to another shadow to lineup his next shot. 

Action: Shortbow attack - To Hit 17, Damage 11 + 9 sneak attack - Second roll 13 for disadvantage or advantage
Bonus Action: Hide - stealth 25

'Something invisible?' Paca thinks to himself. He casts see invisibility so he can try and see what we are in conflict with. He will describe to the group what he sees and exactly where the individual is, then say to Theo. "Hey Theo, take that beautiful instrument of yours and let's get this party started with a bang!"

Action: see invisibility on Paca

Bonus Action: Bardic Inspiration on Theo

Well, looks like talking won’t work, Theo thinks to himself. He brings out his Pepperbox and shoots twice at the creature struggling in the spell.

Pepperbox attack 1: 21 to hit, 19 damage

Pepperbox attack 2: 19 to hit, 16 damage

Nyka, following the disturbance in the vines that now make the entirety of the floor very difficult to move through. You fire a shot, only to find it sail past your invisible target. Unfortunately it seems they were not standing where you believed them to be. 

Meanwhile, Two loud, crashing booms echo from Theo's self made weaponry. Causing a bright flash to burn your eyes as the black powder ignites, sending two small balls of Iron just to the right of where Nyka's arrow had passed.. They both strike! You can hear the very audible gasp of pain from something as both shots dig into their flesh. Causing 35 points of Piercing damage. 

Strider, Using his action to Dash. Just gets upto where the loud bang and sudden flash of light had revealed the position of the current battle. With his two blades at the ready, he seems a little confused but determiend to aid you! 

Praxius is up!

Praxius tries to move and realises his feet are entangled, but it doesn’t matter, the invisible enemy is still within reach. He sheathes his sword before his anger overcomes him and he reaches out to grasp the one who had tried to dominate his mind.

“Stay out of my head!”, he says in a near growl, just as some kind of pixie like creature appears by the person, flanking it.

He attempts to grasp whoever it is and clamp their mouth shut. If he fails, he will try again, and if he does succeed he will keep it grasped tightly so as to not let them speak at all.

And then, the pixie creature that appeared from nowhere explodes as he uses the creature to shield himself from harm!

Free Action: Sheathe sword
Bonus Action: Rage - Wild Surge: 3 (See spoiler)

Action: Attack
Grapple 1 (advantage for rage): Athletics: (15,10)+8 = 23 - trying to grapple and clamp mouth shut
Grapple 2 (advantage for rage): Athletics: (15,3)+8 =23 - trying to grapple and clamp mouth shut
Special: Exploding pixie - DC15 Dex Save (disadvantage if restrained) or take 3 force damage
Special: Rage 1/10

Praxiu's form visibly sweels. His Impressive muculature only seems to grow as a familiar red haze comes over his eyes. He pulls against the vines, which do begin to tear and snap away but not completely as they are still holding him in place. With a wooshing blow of wind, his mighty arms reach for and grasp the invisible foe in a vice like grip. The veins along his bicep and forearm pressing tight against his skin appear like they could burst at any moment. 

Just as the exploding Pixie singes the invisible enemy, Causing 3 points of force damage. 

Kadevii Is up!

Kadevii backs up a bit - it was imperative that he keep focusing on the vines! He reaches out with one wing and slashes, sending a bolt of energy hurtling along the corridor toward his target.

Guiding Bolt - 12 TH, 16 Radiant Damage

A shining bright light forms within Kadevii's outstretched palm, Narrowing their eyes and trying to strike the invisible foe now clutched by Their new ally. A vertible lightning strike of divine power rockets from their palm, unfortunately it sails just over the top of the adversary. Due to their invisible nature and the desire to not cause harm to Praxius, Kadevii's aim was thrown off. 

Paca, 
Narrowing your own eyes, A few choice words of arcane nature leave your lips. Altering your vision so you are able to see your foe as if they were standing in front of you. 

You see a Androgynous looking Hylian, with dark purplish skin and long silver hair hanging from a hooded cloak, wearing what appears to be a very dark variant of studded leather armor. They are viciously pulling agaisnt the large hand covering their mouth but to no avail, unable to best or even match Praxius in strength.