Gaius will hold his action until Shortsword Half-Elf 1 moves.   Then, will take his action.

[[For ready actions, Shortsword Half-Elf is a good trigger, but which action are you planning on?]]

(( Gaius will hold his action until Shortsword Half-Elf 1 moves.  Then will move into range to cast Shatter, targeting Shortsword Half-Elf 2, Robed kobold and spear wielding kobold.  If Shortsword Half-Elf 1 can be included, then him too.  Depending on damage roll, may use one sorcery point to Empower the spell and reroll damage dice.  This is all following Relic's turn which is next.  Area of effect added to owlbear map.  ))

Relic, seeing the dodging half-elf in the middle of the hall between him and everything else, decides to forcefully remove the guy. He charges up to the half-elf and attempts to shove it prone for ease of murdering.

Athletics: 7

[apologies for delay]

The Half-Elf, seeing the great automaton coming at it, tries to angle itself out Relic's reach (Acrobatics: 15) but is unable to get out of the way and falls to the ground. 

Another Kobold, bearing a quarterstaff, can be seen rounding the chamber on the right-hand side and ordering the other shortsword-bearing half-elf to close in on the Warforged. (shatter triggered)

@Gaius, if want to roll your damage. 

(unseen enemies in initiative, awaiting result of Shatter) <--------------
11 Raker
10 Spear Kobold [8 damage]
9 Kobold 1
9 Shortsword Half-Elf 2 [dodge, prone]
9 Robed Kobold
7 Kobold 2
7 Relic 
6 Gaius
5 Kobold Mage
3 Shortsword Half-Elf 1

Gaius watches for a good opportunity.  Seeing the other half-elf close into range he acts.  Shatter is cast to encompass the four enemies facing them in the hallway.  A reverberating BOOM! sounds and blasts the four enemies in the hall with 20 points of thunder damage.

Rolled 8,2,2 on initial roll.  Used 1 sorcery point to Empower the spell.  Re-rolled the 2,2 with an 8,4.  Total damage now 8,8,4 = 20.  DC 14 CON save for half.

Gaius moves a bit as well.

Gaius' spell reverberates throughout the chamber with its empowered status sending a shock-wave through the half-elves and kobolds and bringing them to the ground except for the prone one, damage but still alive.

From the pit in the center comes a creature out of the shadows with sharp claws and large single eye on its head. It opens it maw filled with teeth, lets out of a roar as necrotic energy at Relic

Relic Con Save (rolled in log): 3+5 = 8
Save failed, Take 12 necrotic damage
//please ignore the Gaius CON save I also rolled before that, I messed up on an attack's range

To the South, some minor fighting can be heard.

19, Nothic
13, Kobold 3
11 Raker <--------------
9 Kobold 1
9 Shortsword Half-Elf [dodge, prone], 10 damage
7 Kobold 2
7 Relic , 12 damage
6 Gaius
5 Kobold Mage

Coming out of his hidden spot, Raker moves south to where he is just east of Gaius and he raises his short bow, taking a shot at the Nothic.  As a bonus action, he moves back to where he was and attempts to hide again, out of sight from the corridor. 

Short bow : 17 to hit, for 6 points of piercing damage

Sneak attack damage : 9 additional points of damage

Stealth : 26

Raker's arrow strikes true and plunges into the nothic, causing it to let out a roar of pain.

To the South, some fighting out of sight can be heard.

The half-elf in front of Relic uses half its movement to stand up and attacks the warforged, hitting true with the blade. 

Attack 1
To-Hit: 21
Damage: 6 piercing

(Attack 2 in spoiler, please decide if you'll use shield before viewing)

19, Nothic, 15 damage
13, Kobold 3
11 Raker
11 Kobold 4
9 Kobold 1
9 Shortsword Half-Elf [dodge, prone], 10 damage
7 Kobold 2
7 Relic  <--------------
6 Gaius
5 Kobold Mage

/checking in....

Oh crap... just realized its my turn.

Relic tries to end the downed half-elf (advantage because he's prone, disadvantage because he's dodging, so straight attack roll)

Attack: 11 Damage: 6

Relic's axe strikes out with force but is unable to find purchase on the half-elf.

19, Nothic, 15 damage
13, Kobold 3
11 Raker
11 Kobold 4
9 Kobold 1
9 Shortsword Half-Elf [dodge, prone], 10 damage
7 Kobold 2
7 Relic  
6 Gaius <--------------
5 Kobold Mage

Gaius moves up to a closer position to the hallway and adjust the position of his Mage Hand holding the Light infused rock.

He then casts Witch Bolt at the prone half-elf.  To Hit = 23, Damage = 12.  He continues to hold concentration on his evocation, to maintain damaging his target.

Hope you all had a Merry Christmas.

Small nitpick, moving a mage hand requires an action. So wouldn't be able to do that and cast witch bolt on the same turn. But this area is sufficiently lit with dim light to have vision.

Gaius' magic leaps toward the half-elf with a direct hit. As the electric arc fades the half-elf stills.

The kobold mage can be heard casting a spell, though it seems to be targetting something besides the party.

The Nothic charges at Relic and swipes at him with its claws.

To-Hit: 15, 9 //so both miss

Following up a kobold launches a rock from its slings at Relic to aid the Nothic.

To-Hit: max(23,14) = 23
Damage: 5 bludgeoning

19, Nothic, 15 damage
13, Kobold 3
11 Raker <--------------
11 Kobold 4
9 Kobold 1
7 Kobold 2
7 Relic  
6 Gaius 
5 Kobold Mage

Raker steps to the southeast 10 feet out of his hidden position, pulling the bowstring on his short bow as he moves and launches an arrow into the Nothic from his position of hiding.  He grunts in satisfaction as it seems that the arrow finds its target.  After the shot, he moves back out of sight into hiding as before, in his same position that he started in.

Short bow : 25 to hit, for 7 points of piercing damage and 7 points of sneak attack damage.  

Stealth to hide again : 21

(( Details matter, not a nitpick.  Please return the hand if you want.  I’m afraid of gooning the map again to try on my phone screen. ))

Sorry for the delay. Hope you all had a Happy New Year's Eve. 

As an aside, I don't remember exactly where Kobolds 2 and 4 were on the map (saw them in the fog area) so hoping I got them in the ~right areas.

Raker's arrow strikes true, hitting the nothic dead center as more sounds of a scuffle resound elsewhere.

19, Nothic, 29 damage
13, Kobold 3
11 Raker 
11 Kobold 4
9 Kobold 1
7 Kobold 2
7 Relic  <--------------
6 Gaius 
5 Kobold Mage

Relic decides to rush in and try to finish off the nothic with his axe.

Attack: 16 Damage: Unable to parse dice roll.

A solid hit. Relic's axe takes a chunk out of the Nothic.

19, Nothic, 34 damage
13, Kobold 3
11 Raker 
11 Kobold 4
9 Kobold 1
7 Kobold 2
7 Relic  
6 Gaius <--------------
5 Kobold Mage

Gaius draws his dagger.  He keeps an eye on the other hallway to avoid being surprised from that direction.  He readies an action to strike any enemy that approaches him.