Making a long story short, I have the following situation: my players suspected Niklas from the beginning, and have been taking the stones they found to Ubersreik (taking the rain with them). Now on the latest session, they killed Niklas after his failed attempt to steal the stones, and the players now have all the stones on Ubersreik. One of the players is a priest of Verena, and they hope the priests at the temple can help with finding more info about the stones (what they are for, what's on the marked spot...). Right now my players are in Ubersreik.

So the "grand finale" on the TGS book never happened, and technically the campaign ended, but I noticed they are still expecting a conclusion to this campaign. So I ask you, what do I do?

I thought about mixing in another one-shot adventure, replacing that adventure's location with the Nexus location (the bend on River Tranig).

I have most 2e and all 3e books, so, anyone suggest an adventure to integrate with this? Or any other ideas?

PS. Might be relevant or not, but I suspect they are still going to investigate the "haunted tower", the elven tower where the stones originally laid (I said lightning still strikes the place continually, even though they found all the stones).

_{Well, having killed NK, assuming it's the canon, "his meddling set it off" situation (I used a different villain precisely because he was so obvious, he was a pawn), the situation still exists.}

_{I also had the elf tower have a ghost of an elf who knew about the nexus and the seal etc., knew the right ritual to "settle things down agani". Interacting with that ghost involved being subjected to oodles of ghost wails etc.. In my case it helped there was an elf in party to understand the ghost.}

_{You could set up a situation where misguided priests intend to take the stones to the site and destroy them, to free the area of curse. PC's dealing with ghost realize that will trigger cataclysm, and they must rush to stop the destruction and under ghostly instruction (possession even) do the right "reset" ritual. It makes the finale more athletics rushing and social interaction - can you signal to the priests or get their attention if they are in boat, do you have to shoot them?}

_{You could add more stuff around the lost tower - the nexus leaking is animating dead dwarves and elves to fight or something.}

_{Depending on where beastman, goblin and necromancer threads left off - they could be continued on to add in more oomph.}

I would introduce another npc/monster npc who casts a spell from one of those locations activating the stones wherever they are. They will still affect the area around Stromdorf, except now the PCs need to run back to Ubersreik to pick up the stones.

Essentially this:

* Someone appears to be activating the stones from afar and the PCs need to go back to find them.

NK doesn't need to be the only person who is activating them and skip the part where they need to get glued together.

It seems to me that your players are smart (or cheated/metagamed the plot) and there's no point in stopping now!

My players have derailed many plots, but more often ended up helping some bad guy burn down the town..while the players have to sneak off under cover of darkness Our Gathering Storm ended with NK riding a Disc of Tzeentch into the vortex and taking one of the PCs with him...

jh

This is the problem of the whole Stromdorf setting. It is really bad. Almost everything in the setting is so obviously "in your face/railroady" that every player will see through the whole adventure after a few moments.

What I would do seeing as you have a priest of balance and judgment in your party is this. Use a vision granted by the gods. Something along the lines you see a tall person standing in the ruins of some ancient building surrounded by lightning. The players might ask how it look and so on and they might notice its the ruins near Stromdorf where the stones previously sat.

This might help the party to get focused and move the stones where someone can help them. Maybe you can use the high elve envoy (forgot her name) that is in Ubersreik to give them information about the person. Maybe make it that the person they saw in the vision has something very characteristic about him/her. You might also want to make sure that they know asking someone who's not an elve won't know anything useful about some weird and ancient stone from Stromdorf. Maybe mix in some Omens of Verene like the tipped scale, broken sword or go more subtle but make sure at least the priest player interprets these. If they meet the person in the ruins you can finish the story fast or have a whole new adventure centered around repairing the stone and the magic in it.

In addition I would make it so that Niklas was of course the good guy who wanted to save the day but was struck down by some short sighted adventurers.

I would let the players enjoy that they saw through his trickery and instead let them come into contact with another wizard, who explains to them, that they need to take the stone back to ubersreich. The removal of the stones threatens to open a dangerous rift. They need to put the stone back and perform a ritual to seal it.

They are also contacted by a nobleman who is very interrested in buying the stone for a hefty sum

They can end the story as rich or righteous.