To Nickeline, Hewelathan says, "I think that I'll be stealthy enough without Silence.  Perhaps you could just use your crystal ball to scry on my as I approach the building.  I won't be able to see clearly whether the window is clear, but you could see and let me know.  You'll also be able to see how things go once I'm in the room.  Once I'm out, you could cease the scrying and just join in the the fight to escape from the city."

(Trying to move us along once everyone is ready.)

Once everyone else is ready / spells are cast, here's Hewelathan's stealth roll when approaching the building. Stealth 28

Remember that once he's standing outside the all of the other building, the rest of the party will probably be outside the range of Pass Without Trace, so get into position before he moves across the street.   

Hewelathan is easily able to sneak into the window. None of the spiders pay attention to... well... another spider. He's able to approach the wriggling cocoon without attracting any attention at all.

But... how does he go about retrieving the person? Does he wait for a distraction from outside? Because there is no way that the drider will not notice when spider-Hew starts dragging the person away, no matter how stealthy spider-Hew may be.

Nickeline prays for Hewelathan in Gnomish, "Master of Metal, please watch over that man and protect him as you protect us who delve underground."

Next, she casts Scrying, placing the sensor just inside the window. When Hewelathan gets within 30 ft. of it, she begins relaying what she sees and hears to him. Specifically, she tells him whether there is a clear path from the window to the rescuee. She will also relay any request from Hewelathan to Jodie for a distraction, if one be needed.

OOC:
Curse: 7 --> not observed

Note: Hewelathan would not approach too close to the prisoner or the drider, preferring to hang out at the edge of the room until he's ready to move forward and grab the prisoner and run for it. That's because he plans to be wearing the belt of giant strength (between the 2 spider body segments), and even with the best stealth, a spider can't wear that in plain view of the drider!

The idea was (depending on Jodie's preference) either:

• When Jodie makes a distraction outside, Hew-spider would use the moment of distraction to move forward, grab the prisoner, and take him to the window (or double door if the drider is blocking the window).  The hope is that with everything paying attention to the distraction, he can get the prisoner out of the room before anything notices.  
• No distraction. When Jodie casts Confusion (hopefully with Hew-spider staying in a corner and out of range), he'd use whatever chaos that causes to move forward, grab the prisoner, and take him to the window. In this case, he's just hoping that the spell will help him avoid any interference until he gets to the window.  The drider and spiders will be doing nothing, attacking each other, unable to react, etc.

Plus, of course, sanctuary may help him avoid attacks that actually are directed at him! 

Hildegard waits with Nickeline until the gnome tells her that Spider Hewelathan is in position to grab the prisoner, and then she'll tap her spurs together to summon Perdita, leap onto the nightmare's back, and fly to the window to grab the prisoner and make their escape.

Tamphalic casts gift of alacrity on Hewelathan before he goes and stands ready to cast shatter on the spiders, from as far away as he can.

Jodie casts silent image and creates a 20' outside the building attacking Ruby.  "Make some noise Ruby!"

You don't need to tell Ruby twice... she screams in what sounds a suspicious amount like genuine terror when she sees the attacking giant spider!

Jodie, make a Deception check. Let's see how many of the spiders get cleared out.

(Hmm, Jodie’s deception was 7. Is it really a skill check? Isn’t the spell and reaction enough?)

(I feel like there should be some kind of roll on the basis that just having a convincing illusion appear doesn't necessarily provoke the reaction that you might want... for example, the spiders might just not have any particular reason to care that a kobold is getting eaten by another spider. I would also accept a Performance check if you have a higher bonus, and you can roll with advantage because Ruby is helping you with this)

(18 with Advantage)

Jodie's attempt (with the help of a certain kobold) proves quite successful... the commotion draws the attention of dozens of spiders, which begin to flood out of house and into the street... right towards poor Ruby, who lets out a shriek of genuine terror as she sees the numerous oversized spiders gunning for her!

The drider, meanwhile, seems a bit more wary as it moves to another room where it can get a better view of the commotion. Now is Hewelathan's chance!

Meanwhile... what is the rest of the party doing? And how exactly are you planning to get poor Ruby out of this alive?

From a safe distance, Nickeline watches the giant spiders swiftly catching up to Ruby. 'I suppose I can't just stand by and watch her get eaten,' she thinks. She prays in Gnomish, "Great Armorer, protect our guide through these caves and tunnels; in a way, she does as you do. Please—I trust that you understand the irony in what I am asking of you."

OOC: Casting Sanctuary on Ruby

Quote from Mister_Whisker >>

Now is Hewelathan's chance!

Hewelathan sees the drider leave the room and immediately darts forward quietly to the webbed-up figure.  His Belt of Storm Giant Strength lending strength to his segmented legs, he attempts to hoist up the prisoner in his front two legs.  Then he turns and scrambles back to the window to shove the figure out and exit the room himself.  Stealth 20 (with bonus from Pass Without Trace, also using the correct skill bonus for when he's in this wild shape)

Movement: Using up to 40' of movement walking / climbing, Hew-spider moves forward toward the webbed-up figure and then tries to carry the prisoner to through the window (pushing the figure through ahead of him).
Action: Lift up and carry the webbed-up prisoner.  Athletics 28

(@Weathervision - I took a guess, but let me know if you need any other rolls for what he's attempting here.)

Korba has tried to get himself as hidden as possible in an alleyway nearby ((stealth 24)) ready to cast Darkness around Ruby or anyone else if it looks like it’ll help them to escape.

Tamphalic will wait, for now, with casting any damaging spells; maybe they can get out without a fight.

Jodie smiles as the spiders pour out of the building and Hewelathan can seize his chance.  She uses her control of the illusionary spider to block the spider's line of sight on Ruby and give her a chance to hide or run.  The illusionary spider turns around and flashes it's mandibles towards the groups of spiders, as if to indicate IT'S MY PREY to the rest of the group.  The giant spider back legs appears to be spinning webbing around something....  

Perhaps spiders may be deceived (12) the giant spider caught Ruby or something else...

Yeah... Ruby is running as fast as her tiny little kobold legs can carry her right now... while Jodie is able to successfully hide her retreat behind the illusionary form of another giant spider. Did you guys tell her where to run to?

Meanwhile, Drider's Perception: 23

Quote from Mister_Whisker >>

Yeah... Ruby is running as fast as her tiny little kobold legs can carry her right now... while Jodie is able to successfully hide her retreat behind the illusionary form of another giant spider. Did you guys tell her where to run to?

Meanwhile, Drider's Perception: 9

 So... it seems that the party's plan went off without a hitch, at least as far as getting the webbed-up prisoner out the window. But now what do you do? The street is currently flooded with giant wolf spiders and giant spiders, while a drider is watching the strange situation unfolding below intently.