They explored the passage, and found a spike they'd used missing. The Paladin caught sight of a ghost and ran after it. When she confronted it in the mess hall, it "returned" the spike — denting her shield and embedding it in the wall.
Once the party figured out the first "circuit" or "loop" in the dungeon, they decided they wanted to account for each of the rooms within that area, which meant the audience chamber was next. Now that was my favorite encounter.
Inside, the party encountered the ghost whose "horrifying visage" struck fear (read: the frightened condition) in three of the PCs, and caused two of them to prematurely age twenty years. Not too bad for the gnome. . .
But our human Fighter is now in his forties.
Following the ghost incident, the party began exploring the western portion of the dungeon. They followed a passage into an administrative area, with a bunch of desks and moldy papers. There was a dead end full of mildew-y paper.
They backtracked to an earlier door to find a guardroom, where our Fighter with the compulsive gambling problem scored a couple of handmade dice.
Back in the office area, the party followed a passage that branched between a barracks and a door with a mysterious thumping sound. When the Paladin threw open the door — no thumping sound. It was a fancy bedroom.
The party scored some gold and platinum that had been stashed under the bed and in the desk, respectively, then headed back to investigate the barracks.
While searching the room, the party was ambushed by a gang of ghasts, which outnumbered the party two-to-one. The ghasts got a surprise round.
The Ranger was nearly clawed to death, which was a bad way to start. . .
Despite the initial advantage, most of the ghasts missed with their attacks, and none of the party was easily paralyzed. The Cleric's turn undead wasn't as effective as he probably would have liked, but it did thin the herd a bit.
The Fighter got to exercise his new thunderwave spell as an Eldritch Knight (path opened up at 3rd level), which took out two bunk beds and one entire ghast.
The Druid shifted into a dinosaur and promptly got tangled up in one of the beds. He managed to throw it off and forcibly dismantle it while shredding another ghast. Once she overcame her shock, the Ranger mopped up handily.
There's more to do in Fort Sungard, but the group was feeling pretty confident by the end of the fight with the ghasts. Hopefully not too confident.