(I just checked an it's actually trivial to climb down the rope to the ledge, so lets just assume you all do so.)
Kiric causes an avalanche of rocks to go tumbling down into the abyss below.
As the party gets about halfway down the stone staircase, you notice it in the distance, hidden by shadow of the overhanging rock:
At the edge of sight, a fortress top emerges from the darkness. The subterranean citadel, though impressive, seems long forgotten, if the lightless windows, cracked crenellations, and leaning towers are any indication. All is quiet, though a cold breeze blows up from below, bringing with it the scent of dust and a faint trace of rot.
I forgot to mention, at the top of the ledge there was a cold campfire; Soar quickly surmised that it was left by goblins, as there are signs of charred animal bone and crude spear tips buried in the ash. The fire pit is not recent; it is at least half a year untouched.
Asmodai is modestly stealthy, in comparison to Kiric at least.
The narrow stairs empty into a small courtyard, apparently the top of what was once a crenellated battlement. The buried citadel has sunk so far into the earth that the battlement is now level with the surrounding cave floor. The floor stretches away to the north and south, and it is apparently composed of a layer of treacherous, crumbled masonry, which reaches to an unknown depth.
To the west looms the surviving structure of what must be the Sunless Citadel. A tower stands on the west side of the courtyard.
Soar asks, "does that flooring look sturdy to you? Should we use this rope to secure ourselves? I'm not a stonemason but someone might fall through that. Or do we risk the sound of throwing a stone head of ourselves to see if it can hold weight?" [OOC: if the rope was secure at the top, Soar wouldn't have used her rope there as backup.]
“I could create a tiny earthquake. Maybe not strong enough to cave the place in but strong enough to knock away the weak stones so we know which ones to step on.... or not. I’m not the best at making plans.”
The rubble isn't so bad; most of the worst is in the ravine, not on the courtyard, but there is still plenty of rubble. As Heia walks forward, Asmodai behind her sees something she does not: a suspicious rectangle free of rubble in front of the wooden door to the tower.