The Clay Golem moves five feet west to Q-R:16-17 Dex save 17 and is teleported to 19-8 E-F:1-2 taking 6 Lightning damage. With no enemies within reach it stays there.

Eiren is Up

Eiren maneuvers just briefly (horizontal to T14) before firing off another ghostly claw targeting the flesh golem.

Chill Touch Attack: 13 Damage: 6 necrotic. (Remember that on a hit, the target can't regain hit points until the start of my next turn)

Then he moves in behind the helmed horror (horizontal-S14, diagonal-Q12, vertical to Q9) for a quick strike with his magical rapier.

Bonus Action Attack: 10 Damage: 12 piercing (meant to say +6, instead of +4, but I doubt that hits anyway!)

Eiren casts his ghostly claw at the flash golem, which latches on tight. The Flesh Golem seems to be doing poorly.  Eiren then moves to engage the Helmed Horror, swinging his rapier, but misses the armored automaton.

6 The Flesh Golem goes berserk and moves to S9 and attacks the the Helmed Horror with two Slam Attacks. 1st Attack: 15 Damage: 7, and 2nd Attack: 21 Damage: 15. The First attack hits, but doesn't seem to do much damage, the second attack misses. 

Baik, Corvin, Xavier, and Qu'oth are up.

Xavier will cast frostbite at H1 dc 16 cons save or take 6 cold damage and has disadvantage om next attack

Baik grunts in mild frustration. He points his spear at the helmed horror and almost seems surprised when two black beams lance out towards the helmed horror. 

(Eldritch Blast: first ray 16 to hit damage 10. Second ray 10 to hit damage 14)

"Well that was new."

Corvin draws his warhammer and with a two-handed attack aims to strike down the Flesh Golem. 

Attack: 20 Damage: 4 bludgeoning plus, Divine Strike 8 radiant

Corvin is surprised to find that radiant energy flows through his body adding an extra amount of damage to the flesh golem (if hit). He looks down at his hands after the attack to see the energy recede back into his palms. 

Xavier casts a frostbite at the Helmed Horror. 

H1 Con save 20

But the Helmed Horror doesn't seem to be effected by the cold spell.

Baik is surprised by Eldritch Blast as he didn't really know he could do that, however he even more surprised when the force damage doesn't seem to have damaged the Helmed Horror in the slightest way.

 Corvin takes a five feet step (you didn't say where you are moving to, I will need to know before I update the map) to where he is in range of the Flesh Golem, he swings is might Warhammer and turns the golem into parts.

 Qu'oth is up 

(Thanks for the reminder. Corvin will move to T9)

Qu’oth flies by to harass the helmed horror once more, staying only long enough to help the next person to attack it. Qu’oth then flies back to the center of the room, high up out of reach.

The Helmed Horror swings his Longsword at (1=Eiren, 2=Corvin 1) Eiren Attack: 20 Damage: 6, The sword breaks through Eiren's armor. The Helmed Horror attacks again, this time targeting (1=Eiren, 2=Corvin 1) Eiren again Attack: 16 Damage: 8, missing Eiren because of the Bladesong chant.

 Velmine is up 

Velmine lacks a better plan than doing just the usual. With a step 5 ft. northwest, she can hit the Helmed Horror with her scimitar without having to worry about the Flesh Golem behind it. She does just that, aiming for extreme precision and using Qu'oth's distraction one more time.

Attack: 25 Damage: 26 Piercing

Then, a quick order to her mastiff to see it getting out of the way. "So, here's a general order for you, doggie. Can you keep getting closer to your closest foe and just pestering them? Qu'oth here has been doing it very well. Just avoid the pillars, please."

The command to the Golem has to be even quicker, and the tiefling tries her best. "Hey! Get closer to me! Fast! Avoid the pillars!"

At the end of all that, she still has time to jump 5 ft. northwest right behind Eiren.

Quote from Pertuie >>

Velmine lacks a better plan than doing just the usual. With a step 5 ft. northwest, she can hit the Helmed Horror with her scimitar without having to worry about the Flesh Golem behind it. She does just that, aiming for extreme precision and using Qu'oth's distraction one more time.

 

 The Flesh Golem has been turned into parts (ie killed) if that changes anything. I'm pretty much done for now, and will try to post tomorrow afternoon. 

Quote from Flyingmatthew >>

The Flesh Golem has been turned into parts (ie killed) if that changes anything. I'm pretty much done for now, and will try to post tomorrow afternoon. 

(Not really. The point was about getting out of danger without receiving an AoO, so only the flavor part would be changed.)

Velmin moves into attack range and stabs the Helmed Horror with a solid strike. The Helmed Horror is looking pretty dinged up. Moving again she ends up in P9?

The Mastiff moves to U9 in attempt to follow her masters orders.

 The Clay Golem dashes east along the wall until  K-L:1-2 and the moves south 10 feet to K-L:3-4. Ending his turn.

Eiren is up 

(Confirming that yes, P9 is the spot. I didn't feel the need to actually type it when it was implied through the directions I moved to.)

Eiren engages the helmed horror with his magical rapier, attempting to end the threat quickly.

Attack: 18 Damage: 10 piercing 

Attack: 9 Damage: 9 piercing 

Eiren attacks the Helmed Horror twice. The first blow glances of the armor, but the second attack finally finishes of the battle. 

Everyone receives 320 Xp (Everyone should have 61,250 Xp)

I am dropping you out of combat, but I am going to wait until all of you are about to leave the room before doing the after encounter report as the clay golem may take more damage before you are about to leave. (Velmine is correct about the pillars being the transportation devices.) Eiren decide if you want to go through the double doors to the south, or back where you came from. Velmine give the (or walk it through?) the golem directions to get to the designated exit point. I don't think from where he is now that there is a good route to either location. 

Updating map with the golems current location. 

Quote from Flyingmatthew >>

Everyone receives 320 Xp (Everyone should have 61,250 Xp) 

(Assuming you didn't use my character sheet to say that, I'm proud to announce that I succeeded in adding every single point of XP, as my current amount matches 61,250 XP.)

Velmine looks at the golem, clearly annoyed by the situation of not having a hard time taking it out of the room. She speaks to the group, "Look. If we really wanna do it, it's gonna be easy. Baik does the teleportation thing again, which I'm assuming he can still do, and the golem is out of there in no time. But I know how it is and how he'd rather not waste his magic, but I have no idea how to get it past these pillars without some really complicated maneuvering."

(Now, I do have a question. Do the corners to the pillars also teleport? If not, yes, we can take it out with the complicated maneuvering I mentioned in character. If the answer is "yes, they do teleport," there's no way besides teleporting it away. Either using the pillars as the method, or Baik's Thunder Step, as Velmine mentioned it.)

Quote from Pertuie >

(Now, I do have a question. Do the corners to the pillars also teleport? If not, yes, we can take it out with the complicated maneuvering I mentioned in character. If the answer is "yes, they do teleport," there's no way besides teleporting it away. Either using the pillars as the method, or Baik's Thunder Step, as Velmine mentioned it.)

 I'm not sure what you mean by corners, but this is how it reads ...

(I'll explain it through an example. If Velmine was standing on T4, would she be forced to make a wisdom save? Now, I know the answer because it's right in front of me after you sent the message. Yes, she would, which means that "the corners" I thought of do teleport still. I should've used another word. Anyways, the plan is to either teleport it randomly using teleporters until it can make its way out or Thunder Step then immediately short rest?)