Weasel one fails its save and dies (but only by 1 hp thanks to protector cannons temp hp)

Erix casts a thorn whip, while the badger burrows up and attacks:

badger: to hit 15 for 1 dmg

Thorn whip: 21 for 7dmg

Zoveldra dodges the chittering swarm and strikes back.

Action: Unarmed Strike to hit 19, damage 12 Force

Extra Attack: to hit 18, damage 10 force

The last Swarm is downed, and you are able to wade through the Muck Pit. The sound of more chittering scarabs haunting you as you move. 

After a few more hours travel, you find yourselves at a broad terrace at the top of a massive flight of stairs leading down, at the bottom of which is an even bigger stone door made of mithral and steel inlaid with adamantine runes that seem to glow slightly blue. Eight Deep Gnome guards stand at the gate, the leader calls out, "Who enters Xanxirite, the true home of the Svirfneblin?"

LANDMOP tries to keep herself and her undead out of site. (Thinking zombie for the one that got pulled from the muck?)

The Deep Gnome asks again, "Who goes there!?", more angrily now.

"Sorry, sorry." Elero clears his throat and steps forward. "We've just...been through a lot.  For you, and your people, in fact.  We were given the task of defeating the nearby trolls, and we're happy to report we've done so.  The Slaverers and the Topknots have both been vanquished." He smiles, looks at the others, and then waits for a response.

The guards are certainly taken aback by this proclamation, looking at each other in awe and whispering. The head guard addresses you again, "You must be the party Jimjar was travelling with, why didn't you say so immediately? Come with me."

The head guard and two others lead you through the giant door that opens without any sound. After the door, they lead you through a twisting and turning path that runs between 10-foot-high walls studded with nails. The guard explains that this maze is the city's second line of defense after the Main Gate, then there's the gauntlet. Which you see after travelling through the maze: a wide, winding tunnel behind a gate similar to the one in area 1. In the walls, the guard explains, are spell gems set to blow with powerful arcane energy, thankfully you are friends to the deep gnomes, and won't have to face any of the city's defenses.

After this you come out into another tunnel area, but this one acts as a Reception Hall to Inner Blingdenstone, the main Deep Gnome enclave in Xanxirite. You see many deep gnomes (and a few other Khyber natives) walking around with pickaxes and rope and all sorts of equipment. They chat to each other every now and then, but the sound of industry from all around makes it fairly useless, and they seem to all have a job to do in this great underground city/mine. The head guard explains to you quickly that if you wish to speak to their leader, you need to Diggermattock Hall, (area 14 on the map) and he then heads back out to the main gate.

Alright, so you are currently in the Reception Area (5), and you've been told that Diggermattock Hall (14) is where you'll find the head Deep Gnome. Do you head straight there or is there something else you want to do in this underground city of Xanxirite?

Up to you what you want to do, looking around, there are a few mining companies you could visit; as well as some strange rock-druid types getting around. Or you can head straight for Diggermattock Hall.

I think LANDMOP would like to avoid social contact if possible. Maybe try and find some arcane types, see if there are any spells for trade

Assuming the rest of you follow LANDMOP, he hears of a place within the city where rare mushrooms are cultivated, possibly of interest as spell components. You travel through the Trader's Grotto toward the Cultivation Caves, a cavern filled with stone mushrooms where merchants gather in makeshift stalls amid the stone stalks to hawk their wares and barter with one another. You also see caravans lowering cargo to warehouses carved out beneath the grotto. 

All of a sudden a clanging bell sounds near the main entrance to this place, the deep gnomes around you all draw weapons and retreat as you see a guard stumble back, then rise up in the air. A strange shimmer around him reveals the surface of the gelatinous cube that has engulfed him. Initiative:

Group 1: You all

Group 2: Gelatinous Cubes

You can all act, one of the Gelatinous Cubes have a Deep Gnome guard engulfed, while the other is slowly moving toward other Xanxirite inhabitants, who meticulously move away from the oozes.

Elero will take a shot at the cube that's engulfed a gnome.

Light Crossbow attack: 13 to hit and 9 damage.

The Protector Cannon will hang back, near the party.

LANDMOP will launch.a Blood Bolt at the same one Elero shot

Attack 12 damage 9 necrotic.

And send their undead to try and extract the gnome.

11

1

19

(I think I still have 3)

Erix conjures another giant constrictor snake which starts attacking the cube without the gnome:

To hit 24 for 16dmg
Constrict: DC14 str save or take 15dmg and be grappled.

Gelatinous Cube 2 STR Save: 19

The skeleton's are able to pull the Gnome out of Cube 1, the one who did so takes 9 Acid Damage, while Elero and LANDMOP attack it. Erix' snake bites Cube 2 while Zoveldra lays fists into the gelatinous mess, pulling away with goo on her hands.

The two gelatinous cubes mindlessly attack the closest combatants to them, which is the skeletons, snake, and Zoveldra 

Zoveldra DC 12 DEX save or Engulfed: 18

(I'm going to start copy/pasting the moves rather than contextualizing it for each attack to reduce post size and save me time.)

Engulf:

The cube moves up to its Speed without provoking Opportunity Attacks. The cube can move through the spaces of Large or smaller creatures if it has room inside itself to contain them (see the Ooze Cube trait). Dexterity Saving Throw: DC 12, each creature whose space the cube enters for the first time during this move. Failure: 12 Acid damage, and the target is engulfed. An engulfed target is suffocating, can’t cast spells with a Verbal component, has the Restrained condition, and takes 3d6 Acid damage at the start of each of the cube’s turns. When the cube moves, the engulfed target moves with it. An engulfed target can try to escape by taking an action to make a DC 12 Strength (Athletics) check. On a successful check, the target escapes and enters the nearest unoccupied space. Success: Half damage, and the target moves to an unoccupied space within 5 feet of the cube. If there is no unoccupied space, the target fails the save instead.

The skeletons and the snake will need to make saving throws as well, then you all are up. The Gelatinous Cubes are trying to eat everything around them.

Saving throws for undea

Zombie: 6

Skeleton 1: 13

Skeleton 2: 16

The zombie is immediately engulfed and dissolved.

Both skeletons back away and make shortbow attacks.

(If not shortbow as the stat block, then throwing something)

Attack: 17 Damage: 9

Attack: 20 Damage: 6

LANDMOP fires another bloodbolt at cube 1

Attack: 19 Damage: 10

Snake dex save: 9, Athletics to escape: 19
Snake gets engulfed and escapes.

Erix moves in closer and casts Thunderwave on Cube 2: DC16 con save or take 11 thunder damage and be pushed 10ft backwards.