In the previous session the group entered Rivergard Keep, the second of the elemental evil surface keeps. More by chance than by design they had managed to enter directly into the main building where the boss resided. However the boss was described in the adventure as being a wereboar who was out hunting at night. So the group ended up looting his room without having killed the boss. But that only got them treasure, and not the elemental key they were after.

Searching the building further resulted in them finding a group of commoners sleeping in a dormitory next to the kitchen. They carefully abducted one without waking up the others and questioned him. That gave them a bit more information about the keep and the boss, including the fact that he was out hunting and would return later in the night. But first they searched the great hall and found a letter in which somebody from Red Larch warned about a group of troublemakers, giving the description of the group. They also found a secret door, leading to a staircase downwards.

They followed the staircase and ended up at a landing of an underground river, complete with two rowboats. So they boarded those and followed the river further. However the river was guarded by a group of aquatic ghouls, who managed to topple one of the boats, which made the combat somewhat more interesting. Poppée the wild magic sorceress tried to save herself with magic, which resulted in a wild magic surge that ended up randomly summoning a unicorn. The unicorn was understandably confused by being summoned into water, and decided to "save" Poppée by teleporting her and itself out. But of course the others didn't know what happened, only that Poppée had disappeared. After killing the ghouls it turned out that the way was blocked anyway, by the same sort of portal they had already encountered near Feathergale Spire, requiring the 4 elemental keys to open. (An addition of mine to the adventure to prevent them from randomly wandering into a dungeon of 4 levels higher than the surface keep).

The group went back up into the keep and in the courtyard also found back Poppée. However in preparation of the adventure I had decided to randomize the time of return of the keep boss by letting the group roll for an encounter every time they crossed the way the boss would take home. And by chance this encounter now took place. As the boss had an entourage the fight was challenging, with a priest of the water cult casting sleet storm on the group. The group managed to kill the opponents without waking the rest of the keep up, but the paladin got bitten by the wereboar.

As the boss had the elemental key on him, the group decided to flee and leave the rest of the water keep be. On the one hand that was understandable and consistent with their actions in the air keep. But technically they are skipping a bunch of combat encounters and thus xp. I think I need to make sure that they don't kill the boss of the next keeps too early and rush through the adventure, the adventure isn't designed for that.