"It swallowed Davis!" Vanizi exclaims as she continues to launch her Eldritch Blast at the Hertilod. 
(Spell Attack: 14, Damage: 8 force)
(Spell Attack: 18, Damage: 11 force)
(Spell Attack: 14, Damage: 15 force)
(For the first attack that hits, 1 necrotic from Hex)

Quote from Culuril >>

"It swallowed Davis!" Vanizi exclaims as she continues to launch her Eldritch Blast at the Hertilod. 
(Spell Attack: 14, Damage: 8 force)
(Spell Attack: 18, Damage: 11 force)
(Spell Attack: 14, Damage: 15 force)
(For the first attack that hits, 1 necrotic from Hex)

 

 h...e....l...................p

Round 2 (concluded):
Hertilod attacks the paladin with its claws and maw!
 - Claw Attack 1: 18 Damage: 11
 - Claw Attack 2: 17 Damage: 15
 -  Bite Attack: 32 Piercing Damage: 25 + Poison Damage: 11. If bitten, make a DC 20 Strength saving throw or be swallowed by the hertilod. A swallowed creature has the blinded and restrained conditions, and it has total cover against attacks and other effects outside the hertilod. 
Vesta attempts to immolate the monster, making it once again use its legendary resistances to magic to prevent being engulfed in flames.
Zyl investigates the pools of sludge, finding nothing but pain! 
Davis disappears into the beast's gullet (you can still attack from inside the monster - just at disadvantage...)
Vanizi throws more blasts of eldritch fire at the creature, all three orbs impacting it. 
Legendary action: you can see the monster's gullet contract as it works to digest the halfling paladin! (Davis takes 7 necrotic damage, and the hertilod heals the same amount!)

Round 3: (Map!)
Hertilod moves forward to attack the next creature - Vesta!
 - Claw Attack 1: 13 Slashing Damage: 17
 - Claw Attack 2: 19 Slashing Damage: 16
 - Bite Attack: 30 Damage: 9 piercing + 19 poison. If bitten, make a DC 20 Strength saving throw or be swallowed by the hertilod. A swallowed creature has the blinded and restrained conditions, and it has total cover against attacks and other effects outside the hertilod. 
Vesta 
Zyl 
Davis 
Vanizi

Zyl screams in pain and frustration before running back to the others. "This nasty goop better not get in my brownies! Hey big guy! Hey guys the stick thing isn't over there either but there are a bunch of rocks!"

She will go to the split columns in the middle and throw her greataxe between them at the monster! (like 2 squares above the A2)

Action: attack!

Attack 1: 12 misses

Attack 2: 21 to hit: 11 + 4 + 3 = 18 fire damage

Vesta gets swallowed by the hertilod! (Strength saving throw 11) Writhing inside the monster's disgusting gullet, the sorceress nevertheless does her best to damage the beast from within. She unleashes flames from her hands, giving the monster a wicked case of heartburn.

Burning Hands at 4th level - 20 fire damage + 5 affinity fire damage. DC 19 Dex Save! She will also use 3 sorcery points to make it a Heightened Spell, forcing disadvantage on the hertilod's save! 

Davis feels a foot hit his head as someone else is swallowed!

25 dmg: 23

15 dmg: 17

16 dmg: 17

21 dmg: 12

Vanizi maintains her position, again casting Eldritch Blast.

(Spell Attack: 13, Damage: 14 force)
(Spell Attack: 18, Damage: 15 force)
(Spell Attack: 12 - nat 1)
(For the first attack that hits, 4 necrotic from Hex)

Round 3 (con't): (Map!)
Hertilod moves forward to attack the next creature - Vesta!
 - Claw Attack 1: 13 Slashing Damage: 17
 - Claw Attack 2: 19 Slashing Damage: 16
 - Bite Attack: 30 Damage: 9 piercing + 19 poison. If bitten, make a DC 20 Strength saving throw or be swallowed by the hertilod. A swallowed creature has the blinded and restrained conditions, and it has total cover against attacks and other effects outside the hertilod. 
Vesta burns the creature on the way down its throat! (Honestly, I see no way for the creature to dodge your flame attack from inside, so it will take full damage =D
Zyl rushes back to the fight, hurling her greataxe at the hertilod but missing it. (What are you throwing for the second attack?)
Davis thrusts the greatsword inside the monster, dealing an incredible amount of damage to the creature!! (The hertilod must make a DC15 Con save because of this damage! {25} If it fails it regurgitates all creatures in its gullet, and they land in a space within 10 feet of the hertilod with the prone condition.) 
Vanizi continues the eldritch assault, but only 1 blast hits it this time...

(Uh oh!! It keeps you in there!) Legendary action: Fresh meat! Vesta takes 9 necrotic damage as she gets digested!

Round 4: (Map!)
Hertilod moves towards Vanizi and attacks through the opening! Vesta and Davis each take 19 poison damage from the digestive juices...
 - Claw Attack 1: 22 Slashing Damage: 22
 - Claw Attack 2: 17 Slashing Damage: 15
 - Bite Attack:  Attack: 14 Damage: 14 piercing + 9 poison
Vesta (swallowed)
Zyl 
Davis (swallowed) 
Vanizi

Zyl shrieks in fairy baker language. Whatever that is.

Action: attack (range)

Attack 1: 17 to hit; 10 slashing + 2 (elemental cleaver) + 3 (rage bonus) = 15 total fire

Attack 2: 17 to hit; 12 slashing + 4 (elemental cleaver) + 3 (rage bonus) = 19 total fire

The fairy barbarian's infused greataxe hits the lizard creature twice, killing it! Moments later, Vesta and Davis crawl out of the hertilod's moth, and Davis is clutching a rod-like greenish stone - the 2nd piece to the rod! This piece can be used to create an Arcane Gate once per day. You also find a Ring of Regeneration inside the hertilod, on a finger that is slowly regenerating a hand...

(Congratulations on finishing off the monster and completing this quest! You each gain a level (should be at 13th level) and can travel back to the Sigil stronghold to rest and discuss this adventure with Aludriel.)

"Hey the stick thing! GREAT! Let's get out of this super stinky place!" Zyl kicks the carcass of the creature as she then flutters back out of the heart thing and on her way back home. "Definitely need to make more brownies..."

"Good work!" Vanizi says to everyone. "And glad you two weren't swallowed permanently too!" she adds to Vesta and Davis. Having stopped holding her breath, she can't help but agree with Zyl. "Yea, let's get out of here fast." 

She makes sure the new rod piece and the ring are picked up, if nobody else does that, before they go. "Who wants this rod piece? Will they all help locate other pieces?"  She then considers the ring. "Feels like Davis is the one jumping into taking most the damage. Maybe he should take the ring." She then looks at Davis. "If you would use it." 

Davis rubs some unknown goo off his arm from the belly of the beast as he crawls out, agreeing they should vacate this foul place asap!

[I would use the ring, he has an attunement slot open]

Vesta crawls out of the dead monster and tries to wipe digestive juices off her robes, but she's absolutely covered in slime. 

"I am going to take an hour long bath when we get back!" she cries. "Let's tell the crew we found what we were looking for and will be returning home."