Rictor wrinkles his nose as he smells cow dung from the southern tunnel. He nods toward the north eastern tunnel. "I say we take out the goblins first and take care of the cattle later."

Southeast it is

Keth nods in agreement, "The quiet tunnel does seem more likely. Those goblins would be spooked even if they did not see us, therefore they would be doing what they can to stay quiet. Leads head on." He begins lightly stepping to the northeast tunnel.

The party moves to the northeast entrance. Val seems a bit confused but gets right orientated after someone steers him in the right direction. 

You travel about 20 feet down a short tunnel from the entrance area. The torch light bounces off the wet walls of the interior showing you a much larger area past the cave. You hear this as you travel forward: https://www.youtube.com/watch?v=bVIJCHzWNkI  the sound slightly echoing through the new cavern you find yourself in. 

The 20 ft. you travel seems to be going down a steep incline. The incline is covered here and there with loose gravel which you seem to move at ever step. 
(Dex saves everyone to keep from sliding)

The incline opens into what appears to be a cavern. Opposite the tunnel you see a cave wall, approximately 15 feet from the tunnel.

To the left it seems it opens up a bit into a cavern. The torch light doesn't give you a great view of how big it is but there is something on the floor ahead in this room. The torch light reflects off it.

To the right seems to be a smaller cavern but it is at an incline and goes down approximately 30 ft. and will take some time to traverse without falling or sliding. 

https://docs.google.com/drawings/d/1QRq1iq526iiwTxFADKVfKM3oJ0TPgYC4cUVkzKSzpig/edit

Just as the party gets to the end of the tunnel, an arrow comes out of the darkness from the left aimed at Keth.

Attack: 13     Damage: 7   (Keth, make a Saving Throw vs. Poisons please)
Initiative for all please.

 Keth dex save from sliding: 17 and in case Danger Sense helps for advantage: 18

Keth grunts as the arrow grazes him, his body attempting to shrug off the poisonous effects: 21

Initiative: 14

Val Dex save 15 

initiative 4 

Rictor

Dexterity Save: 12 

Initiative: 18

(Sorry, everyone, I'm having trouble keeping up with the posts.)

Dex Save 23

Initiative 18

Goblin Initiative: 10

Combat Order:
1) Rictor 20
2) Goblins
3) Celeste 9 (higher dex score)
4) Keth 9
5) Val 4
6) Clay

Each of you make it down to the bottom of the tunnel, scattering loose gravel and sand as you go down, without sliding off your feet. Clay seems to linger behind.
The 4 at the bottom see at the bottom of the smaller part of the cavern, some 30 ft. below you,  3 goblins armed with bows and are pointing them at the party. 

(OCC: all of you may post your actions I will put them in order in my next post)

Rictor sees the sneering face of an armed goblin and immediately feels revulsion, casting Hex on the goblin on the middle as a bonus action.

Pulling out his revolver he aims at the one in the middle and casts Scorching Ray, sending a beam of fire at each goblin.

Attack (Goblin 1): 23

Attack (Goblin 2): 17

Attack (Goblin 3): 21

Quote from stronglyworded >>

Rictor sees the sneering face of an armed goblin and immediately feels revulsion, casting Hex on the goblin on the middle as a bonus action.

Pulling out his revolver he aims at the one in the middle and casts Scorching Ray, sending a beam of fire at each goblin.

Attack (Goblin 1): 23

Attack (Goblin 2): 17

Attack (Goblin 3): 21

 All 3 attacks hit. Roll damage.

Damage (Goblin 1): 6

Damage (Goblin 2 - assuming this is the middle one with Hex on it): 11

Damage (Goblin 3): 8

Val will lean over the side and fire his rifle at one of the goblins, and start working his way around to the bottom.

Attack: 10 Damage: 8 
 

Celeste will also try to take a shot at one of the goblins before bracing herself to fire again.  She would prefer not to get up close and personal with the foul creatures.

Attack: 15 Damage: 14

Keth grunts as he notes the goblins still much below the group. He looks down the incline and back at the group, his options limited as his rifle is with his horse.

The man's eyes narrow as his breath quickens, his senses heighten as the world melts away to only the goblins before and below. He sheathed his long knife and hurtles himself down the embankment at the goblins.

As he closes in he swings his tomahawk.

Tomahawk Attack: 18 Damage: 8

(Also Rage)

Rictor takes out his pistol and 3 bolts of hellfire fly from the pistol, 1 striking each Goblin.  The bolts hit 2 of the Goblins and they burst into flames are almost immediately consumed by hellfire. 
The second Goblin screams out before the hellfire hits it, with a flow of dark energy striking it, and it starts to fall. Once the bolt of hellfire its it the Goblin almost becomes ash.
The 3rd Goblin is hit with the hellfire bolt and screams in agony, dropping it's bow. Flames leap across its body as it points towards the party and says "Taqua Irrima". The goblin turns to Disengage and rushes south into the darkness.

Celeste aims her Winchester but seeing the goblin has fled, holds her shot. Everyone else holds their actions as well.

(Ruling: Since Disengage does not provoke an attack of opportunity the party holds their shots)

The party stands for a moment, watching and listening in hopes of getting a shot at the goblin when they hear this: https://www.youtube.com/watch?v=DmSAGoLhoyw
After a couple seconds they see the darkened floor of the cavern they are looking into start to move. Each of you realize its not the darkness as you see a MASSIVE SWARM of RATS heading towards you. There are so many you can't count their numbers but with their squeaking and their collective movement echoing through the cavern it almost sounds equal to that of a Thunder Storm. The mass of rodents easily traverse the cavern walls and their wet skin glistens in the torch light. They will be upon you within a second. 

Reactions 

OCC/Side Note: Everyone please make a Intelligence roll as well.

Val intelligence check 22 

Rictor freezes as he hears the rats swarming closer. It was a familiar sound to a street urchin; the slums of New York which Rictor once called home were lousy with the rodents. He was instantly brought back to those troubled times. He also didn't want thousands of rats ruining his fancy new duds!

Intelligence Check: 18

If he's able, Rictor casts Thaumaturgy to cause a tremor to run through the ground thirty feet around them in the desperate hope that the rats will avoid the (harmlessly) trembling ground.

Intelligence - 6

Celeste yells and prepares to run.  Rats!  Disgusting!  How did they all get here?