(The arrow slit is ten feet off the ground. A grappling hook would take a Dex check and risk noise, but would not require a Catapult spell. Boosting the 31" tall, 30-pound kobold would require a fairly tall person – how tall is Kimberley? Or a little climbing. Or perhaps a medium-sized person could stand on the shoulders of another medium-sized person?)

((Metagaming Note: Bryony has the class trait of Second Story work so climbing doesn't take her extra movement.))

"Maybe someone can lift me or Jurgen, and we climb up to the arrow slit?" Bryony says quietly. "I'm pretty decent at climbing. I climbed trees all the time as a kid. That's how I broke my arm once. Uhh...not that I would do that this time of course."

Kimberley mused, " I'm not that strong but I could probably take the weight if you want to use me as a 6 foot ladder."

(With Kimberley's help, Bryony could easily climb the heavily-weathered wall as far as the arrow slit without rolling. She will need to roll a Stealth check, however. And the slit is too narrow (about 4 inches wide) for even a small halfling to squeeze through. Jurgen could maybe squeeze through, if he were to take his armor off and roll a successful DEX check together with a Stealth check.)

Looking at the arrow slit Jurgen says "Hmmm. Yeah, I could fit through there. Then I can open the door from the other side." 

(OOC @DM Does it look like a shield could fit through?)

Jurgen will Doff his armor but keep his (size appropriate) shield and long sword with him as he tries to quietly move in through the arrow slot. 

DEX Save 10

Quinn waves his hands in protest, but it's too late. He shakes his head and turns to Syzygy trying to communicate what's going on with hand gestures.

Performance check: 10

Quinn, not known for his performance art or miming, tries his best. He makes a set of horns with his index fingers, mimics climbing up the wall and motions as if something were diving into a hole. In this moment he feels quite embarrassed and a bit stupid so he gives up his performance and turns to watch the little kobold attempt to climb the structure.

He draws his bow and aims it at the murder hole, just in case.

Jurgen scrambles up, a bit ungracefully, (and presumably with some help), and squeezes into the slot. 

But then he freezes. Peering into the dim interior, he sees... a raucous, messy dinner party. The western portion of the large hall ends in a wall of rubble, but the remainder is still intact. Evidently, this was once the castle’s banquet hall, with a soaring ceiling twenty-five feet high. Two large wooden tables with plain benches stand in the middle of the room, and a brass brazier full of glowing coals is tucked into one corner. Dirty dishes, half-full stewpots, moldy heels of bread, and gnawed bones cover the tables. A half dozen goblins scuttle about while a tough-looking goblin barks orders.

Jurgen was not exactly quiet climbing up and into the narrow crack, but the goblins within are oblivious. They have not yet spotted him in the arrow slit.

Jurgen will stealthy move to the door and go thru. 

By squeezing the rest of the way through, Jurgen will put himself in full view of the goblins to get to the door. The only thing he has in his favor is the chaos in the room as the goblins eat and bicker (they're currently arguing over whether the dishes need cleaning.) It'll take both stealth and luck to make it across those fifteen feet undetected. 

Make a fresh Stealth check – at disadvantage due to the immediate line-of-sight – if you want to attempt it. (Fortunately, the DC is only 9.)  Otherwise, you can safely retreat.

Jurgen, not used to being out if his armor tries his best to sneak past them. He focuses on where he steps and to not make any sudden moves or sounds. He reaches the door and opens it carefully. 

Quinn watches as the little kobold squeezes himself into the slit in the walk. He honestly didn't think the little kobold could fit in there. Now the idea of him being trapped in the castle sends him into a a panic. He turns to Syzygy and motions for him to come over quickly. 

Quinn switches to his battle axe and slowly walks over to the Kimberly and Bryony. He's mindful to keep his back to the wall.

None the wiser as to what is happenign inside, Kimberley gives Bryony a thumbs up and leans back against the wall.

Syzygy, slightly confused by Quinn’s gestures, scuttles over. “We need to work on that.” He whispers.
syzygy looks above “he hasn’t has he…?”. 
syzygy casts alter self and his face warps into the smug egomaniacal face of Glasstaff. 
“Someone give me a boost so I can keep an eye on the bugger.”  

athletics: 18

To the watching party, Jurgen squeezes through the gap and vanishes. Then you wait.

Inside, somehow, Jurgen drops to the floor and just strolls along the edge of the raucous dinner party, opens the door, and exits, without being spotted. It was partly just pure luck, but in the end, the goblins were too busy shouting, arguing, and eating to notice the small intruder wandering through. 

Assuming Syzygy/Glasstaff gets a boost, he, too sees the dinner party inside, although he's too late to see where Jurgen went. (Syzygy: Make a Stealth roll.)

Jurgen finds the space beyond the door is filled with debris. A heavy curtain obscures the area to the north, and there appears to be a path through the crumbling mess to the east.

Unless Jurgen has any other business here, he unlatches and opens the door to the south.

That is exactly what Jurgen does. He opens the door to his friends. He then dons his armor (5min). and brings Draco around to him. In hushed voice he tells them the details of the inside and the goblins therein. 

In a hushed voice, Bryony says, "We could catch them by surprise if we're quiet."

Quinn is startled by Draco sneaking up on them heading for the group. Then he notices Jurgen has emerged safely from the castle. He tugs on Syzygy/Glasstaff's robe and points at Jurgen. Quinn rushes over just in time to hear Jurgen spill all the details of what he saw within.

Quinn nods in agreement with Bryony.

"Aye, that's a possibility. Though our friend, Syzygy...I mean...Glasstaff might have an idea of his own." 

Stealth 12.

Syzygy looks down, confused to see his friend this side of the wall, as much as his friend might be confused to see Glasstaff. 

Syzygy finds his feet and brush his grey robes. “I could be a lure for a trap perhaps. A surprise imdeed. Or a back up plan. Either way I’m growing tired of negotiations and bargains. Perhaps we get in an advantageous position and I announce myself as having word from The Spider. And then we pounce.”