"That thing is an aberration!" 

"That's what he said!" Camilla confirmed.

"By all that's unholy, what is that thing?" Tarak questions as the transformation takes a moment to register.  Then his focus and rage solidify back onto the creature ahead and his fury rises once more.

Attack: 6 Damage: 6

Additionally, (assuming he hits) he adds on a Divine Smite doing 15 radiant damage and an extra 5 radiant damage if the thing is undead or a fiend.

(This post assumes I am allowed Round 3 and Round 4 actions)

Following up his last divine strike he swings his huge double-bladed broad axe one more time, with all his might.

Attack: 17 Damage: 8

Round 4
Markus 21, Tarak 19, Camilla 19, Morrigan 18, Ixthiuitol the Devourer (AC15, HP 25)17, Zook 13, Sydril 8

Tarak’s divine might lights up the room as you feel the aberration scream in pain...though you only seem to hear that scream in your heads! Second attack misses. 

Round 4
Markus 21, Tarak 19, Camilla 19, Morrigan 18, Ixthiuitol the Devourer (AC15, HP 25)17, Zook 13, Sydril 8

Intelligence:2

Markus recklessly attacks with both axes!

Attack: 20 Damage: 12
Attack: 16 Damage: 11

Sydril scrabbles to pick up her rapier and avoid the monster.  

Round 4
Markus 21, Tarak 19, Camilla 19, Morrigan 18, Ixthiuitol the Devourer (AC15, HP 3)17, Zook 13, Sydril 8

A pair of solid hits!

Zook acid splashed again.  Oh to have more spells slots. 

DC 13 Dex save:  3 acid damage 

Round 4
Markus 21, Tarak 19, Camilla 19, Morrigan 18, Ixthiuitol the Devourer (AC15, HP 3)17, Zook 13, Sydril 8

Ixi DEX save: 8

In response, the aberration screams into your minds once more...this time, though, it friggin' hurts!
DC 13 INT save or 11 psychic damage. Anyone who fails is also stunned until the end of the creature's next turn.

Sydril Ice pick in the brain save:  9

Sydril grabs her head, a sound of pain escaping her.  She stands there, helpless.

INT save: 22

WHEW!

Camilla winds up and goes for the kill shot! Can she do it!? WILL SHE DO IT?!

YERG!! Attack: 17 Damage: 7

YES!

"Take THAT, mother ****er!" she yells.

The tentacled horror's mental scream of anguish goes silent as the arcane bolt slams into it, slowly it writhes on the ground, crackling and sizzling as it become ash. Across the way, the unconscious Jalie begins to stir, sobbing and shaking at the ordeal she has endured.

Congratulations! You have survived the Vault of the Devourer!

First of all, welcome to Level 3 for any who want to keep their characters. Secondly, know that while in town, bakery treats are free courtesy of Jalie! Also, searching the room and the dead (or what's left of them in DT's case), you locate 120 gold pieces, a pair of [Tooltip Not Found], a conjurer's spellbook (on DT) with the following spells: absorb elements, find familiar, grease, unseen servant, dust devil, flaming sphere and misty step; and a 3 potions of healing. 

When the group returns to town with Jalie, they are met with much rejoicing and partying. However, as the revelry wears on, Intun Alderson pulls you aside to express his concerns about whether all the rooms of the vault were inspected.

"It's a tower....what if something even more wicked lies elsewhere inside?"

The Ruined Tower of the Tempest Mage, Part 2: The Clockwork Laboratory

Taking Intun Alderson up on his suspicions, the party returns to the Ruined Tower of the Tempest Mage, retracing their steps and finding a room that they chose not to explore earlier in their haste to find the missing girl. In Area 8, you all find a hallway that ends in a brass door, covered in knobs, handles, clockwork gears, blades, and threatening looking tubes. It appears to be a vault door of some sort; one that is clearly trapped.

Tarak waits nearby the others, greataxe grasped in his big hands.  He is constantly on the move, as is his habit, shuffling about, waiting for someone who knows about these things to give the strange door a check over.

Before heading toward the door, Zook remembers to cast mage armor.

Zook then looks at the door from a distance...."Hmmm...most troubling....let me see what I can see...."

He sits down and ritual casts detect magic before taking his next actions.  

"Look i'm sorry, ok?" Camilla pleaded, standing near the group talking to her white cat, who was looking very pist.
PFRT!
"Oh, come on, Poopy. Look, don't take this the wrong way, but you're expendable! We lived, didn't we?"
FFFT! FRT!
"Fine. Fine. You're right. I'm sorry. I won't do that again. Ok?"

Camilla rejoined the group. 

"Oh! A door!"

Sydril waits with Tarak, hoping someone can figure out a way through this imposing door.

As the gang assembles around the door, watching Zook slowly cast his ritual spell, the gnome looks up, letting out a slow whistle. That door is lit up like a Christmas tree.....mostly evocation magic.