The party quibbled about Jinny Beau’s plans. They called the Hangman and asked her how difficult it’d be to produce a projector for displaying images on the dome’s surface. She said she’d work on the problem, but it’d take time. The party went ahead with what Jinny Beau wanted.
The whole thing was a debacle. For some reason the party assumed their assassination targets would be on the top floor, so they ran up the first flight of stairs they saw. The gas coming into the building gave them a good solid element of surprise, but since their targets WERE on the first floor, they had plenty of time to recognize they were in danger and evacuate to safety while the party poked their heads into every room except the ones on the first floor.
The top floor contained the wives and daughters of the clan, and the party DID manage to kill one of the Duke’s sons while he was spending time with his wife.
After running up and down the building several times, forces started to gather outside for a counterattack. The party set some explosives which didn’t demolish the building, but did cause it to sag and twist in a way that made it feel completely unsafe to inhabit. Then they escaped into the sewers.
The whole thing was basically a waste of time aside from the 30,000cc worth of treasure they managed to haul out, but that’s probably cancelled out by the fact they put the people they wanted to kill on high alert.