Syd replies without a trace of humor in his voice, "Anything that stands between me and food has a death wish."  He would be surprised to learn that he is unwittingly quoting an ancient orcish aphorism.

He then opens the final door. Dramatic music swells to a crescendo.....

"Let's finish this off and get some food." Ollezall fingers his mace, with no intention of using it.

The party bravely enters the final room of the lower layer.  Resolute in their desire to discover its contents quickly, lest they become angry due to their increasing hunger, they being their examination in earnest.  The air here smells of astringent chemicals.  Long wooden tables stretch across the room, laden with vials, beakers, and flasks holding various liquids and powders.  Books are stacked between the glassware and chemicals.  Yellowed paper charts and blackboards full of complex formulae cover the walls.

(As usual, let me know what you would like to do and what checks you'll be making to achieve it.)

Dyumi will try to see what the papers say.

17

Ollezall will use his herbalism kit and skill in medicine to examine the liquids and powders.

Medicine 13.

Ollezall will survey the room for points of interest; Ollezall is looking for objects hiding in plain sight. Ollezall will use Syd's lantern as an aid to reveal hidden messages, or objects that would otherwise be invisible to the naked eye. 

Perception 12

Mohdrak paused his stirring with a confused look. 

'Say what now?' He stared at the little, batlike Cumin. 'Are you sure they are not there?'

He called out to the other servant. 'Coriander! Did anyone walk by while we were preparing dinner?' 

Between their respective skill sets, Dyumi and Ollezall can recognize that the books here cover chemical science and alchemy.  They determine that the main goal of the research here was to transmute various materials into gold.  Judging by the numerous scorch marks and acid burns on the furniture, the laboratory was the scene of several spectacular failures.

Ollezall notices two other noteworthy items.  First, there are four clay figures resting on a table in the middle of the room.  They range from a rudimentary, barely humanoid shape to a small, winged body so lifelike that it almost appears to be a real creature that is merely asleep.  Second, a book that is nearly identical to the one the party found in the study is propped up against a large beaker.  The only difference you notice is that it has a prominent letter 'B' on its spine.  Mordenkainen is still glaring at you from the cover.

Quote from Furujiru >>

Mohdrak paused his stirring with a confused look. 

'Say what now?' He stared at the little, batlike Cumin. 'Are you sure they are not there?'

He called out to the other servant. 'Coriander! Did anyone walk by while we were preparing dinner?' 

Cumin responds, "Oh yes, I'm quite sure.  They're definitely not in the study.  I think I heard some noises coming from down the stairs, though.  Our masters generally discouraged us from travelling throughout the mansion too much without being directed to do so, so I'm afraid that I can't offer much insight into what might be down there."

And from Coriander, "Yes, yes, master minotaur!  I saw two of the cats heading down the hallway!  Do you want me to track them down for you?"

Cerlinde will also examine the laboratory and look at the book.  With proficiency in alchemist supplies and the herbalist kit, she will examine everything.  The creature that looks like it is almost finished- What is the final step required?   
 
(Assumes help from the others)

23 arcana

Cerlinde can tell that these are figures used for creating homunculi, with which she is familiar (pun intended).

Several of the reagents strewn about the table are quite valuable.  As you peruse the items, you find that you can gather about 50 gp worth of alchemical materials.  With the help of Ollezall and Dyumi, you discover that, in addition to the alchemical supplies, two of the vials on the table contain potions of healing.

Syd will look around for trapdoors, hidden alcoves, invisible chests, false-bottom drawers, fake books, mystic portals and, you know, clues.

If he finds nothing he will entertain himself making vaguely pornographic stick-figure doodles on the chalkboard.

Investigation 3

Perception  17

Quote from Syd_Wartnose >>

Syd will look around for trapdoors, hidden alcoves, invisible chests, false-bottom drawers, fake books, mystic portals and, you know, clues.

If he finds nothing he will entertain himself making vaguely pornographic stick-figure doodles on the chalkboard.

Investigation 3

Perception  17

Syd finds exactly nothing, aside from a growing feeling of hunger as the aromas from the kitchen drift down the stairs.  He does, however, perceive that he is very amused by the drawings he has added to the chalkboard.  Evidently, Syd's literary finds from earlier in the adventure have inspired his artistic side!

Quote from EtyenAndiros >>

two of the vials on the table contain potions of healing.

" I have my eye on at least one of those potion of healing." Ollezall will say. " We should also gather these 'blank' books with the lettered spines; I smell a clue... And dinner!"

Ollezall will make a medicine (and insight?) Check on the simulacra to see if it's alive or playing possum

Insight 25

Medicine 13

 (That was awful)

If I don't try, my passive insight is 17. Your discretion.

Out of curiosity, Syd will direct the lantern beam onto one of the blank pages of the Mordekainen book.

Cerlinde will also examine the book and nearly finished Homunculus, and will put the book in her pack with the others

11 investigation 

“Ollezall and Syd- or dyumi- why don’t you take the potions of healing.  I have one from the wilderness patrol still.  I’ll collect these reagents for the party fund.  I wonder if this homunculous is nearly finished if we could wake it? L Cerlinde says, as she puts the reagents carefully in a cloth pouch.   She then quickly draws the room and the layout of the laboratory on her map. 

“If that’s all down here - let’s go see what’s cooking!”  She heads out and up the stairs.  

Ollezall and Syd both have very good ideas, but will likely be slightly disappointed with the outcomes.  Ollezall is able to ascertain that the clay figures, lifelike though they may be, lack any vitality.

(Even though it was never stated by the DM that this book was blank, let's go with that.)  Upon shining the lantern's light upon the empty pages of the latest volume in their set of Mordenkainen's greatest hits, Syd reveals the same nonsensical, repeating text that was found in the first one:  'Lorem ipsum, etc., etc.'.

Satisfied with their work thus far, the party ascends the stairs to find out what Mohdrak has been up to in the kitchen.

(I'll pause here to allow Mohdrak to describe what he's doing prior to the party's reunion!)

Quote from Tesservett >>

Cerlinde will also examine the book and nearly finished Homunculus, and will put the book in her pack with the others

9 investigation 

“Ollezall and Syd- or dyumi- why don’t you take the potions of healing.  I have one from the wilderness patrol still.  I’ll collect these reagents for the party fund.  I wonder if this homunculous is nearly finished if we could wake it? L Cerlinde says, as she puts the reagents carefully in a cloth pouch.   She then quickly draws the room and the layout of the laboratory on her map. 

“If that’s all down here - let’s go see what’s cooking!”  She heads out and up the stairs.  

 Ollezall takes a potion; " I'm not hoarding these, if you need a potion or I spot you need healing I'll freely give them. To me , I consider this treasure is all"

"Wake it? Okay... " Syd says.  He pokes the lifelike homonculus with a thick finger.  "WAKE UP!" he cheerfully hollers.

Quote from EtyenAndiros >>

Quote from Furujiru >>

Mohdrak paused his stirring with a confused look. 

'Say what now?' He stared at the little, batlike Cumin. 'Are you sure they are not there?'

He called out to the other servant. 'Coriander! Did anyone walk by while we were preparing dinner?' 

Cumin responds, "Oh yes, I'm quite sure.  They're definitely not in the study.  I think I heard some noises coming from down the stairs, though.  Our masters generally discouraged us from travelling throughout the mansion too much without being directed to do so, so I'm afraid that I can't offer much insight into what might be down there."

And from Coriander, "Yes, yes, master minotaur!  I saw two of the cats heading down the hallway!  Do you want me to track them down for you?"

'No, that won't be necessary.' The minotaur cook replied to Coriander's question. Mohdrak would not admit it but he would be lying if he were to say he was not a tiny bit worried. If the others had ventured out of the study to some other part of the manor, he could track them down but that would mean leaving the food on the fire. And an unsupervised fire is a dangerous fire, a mentor of his used to say. He could send Cumin or Coriander or both but he imagined they would not be faster at finding them than he would.

Mohdrak scratched one of his horns until he suddenly snapped his fingers: a solution had popped in his head. Well, no so much a solution as something that would circumvent the problem but it was something his mother used to do to call all family members in during feasts. He instructed Cumin and Coriander to bring the various dishes while he himself carried the large pot stewing with meat and placed it on the table. He took the lid off and sniffed the aroma.

'Yeah, this will work.'

Modrak opened the doors leading to the hallway that connected with the study. He positioned himself just right and using his shield as a makeshift fan, he wafted the smell of warm meat and vegetables out the dining room and into the rest of the manor.

(You heard the minotaur, people, dinner's ready!  Or, to borrow a phrase from former professional wrestler and current Hollywood icon, Dwayne 'The Rock' Johnson, aka The Brahma Bull, "CAN YOU SMELLLLLLL, WHAT MOHDRAK... IS COOKING?!")