OOps, forgot to mention what was BEHIND the Math Door:
The players find a small arcane laboratory/torture chamber, with numerous letters in a strange language and a mysterious bone artifact. They also find tunnels underneath that open up into the countryside, along with a single ghoul, who they slay.
En route to Tidewater, they stop to show the bone artifact to Rosh, the naive, heroism-focused cleric of the Singer that saved their corpses from the mummy’s tomb. He destroys it and says “It was probably bad.” and then rides north to try to find the Master. The party isn’t sure whether to worry that he’s secretly evil, or worry that he’s dumb and heading directly towards evil. They shrug and move on.
En route to Tidewater, they stop at Nobridge, the city they saved at the beginning of the campaign, and talk to Lord Bightsword, since he’s holding court. In fact, Magnar insists they wait politely in line, as their issues are no more important than any peasant’s. Brightsword tells them that the elf is problematic, but not to worry, as he’s talked to the Princess of the Mountain (the nickname for the local ruler) and she’s hired a specialist to help with the ensuing diplomacy/intrigue. The party interprets specialist to mean torturer, and are upset.
En route to Tidewater, Magnar convinces Killian that the best way to investigate the Black Ships would be to don disguises. Killian will go as Magnar, and Magnar will pretend to be his servant. Since Magnar has been reincarnated since the last time he was in the city, no one will recognize him. Killian agrees to the plan, only to forget what exactly this achieves.
They put on their disguises and go to find a captain from the black ships. After asking around, they locate the tavern where he is meeting various merchant lords. Killian, as Magnar, puts on his metaphorical Arrogance Hat and strides to the front of the line, demanding entrance, because Killian knows that’s what Magnar would do. Several insults later, this escalates into a tavern fight, or would’ve, if Tyr didn’t just Sleep most of the occupants. They threaten the various merchant-lords and throw them out.
The Black Captain laughs heartily and introduces himself as Vladimir. He tells them about the Glorious and Eternal Empire for a bit, and the PCs realize that whoever wrote the letters to the Master that they found in Lastfall’s basement was from the Solanum Empire, since the letters use their dating system. (Note that this is their third idea, after “The fact that the numbers are bigger means the letters are from the distant past! That they refer to current events means time is cyclical and history is repeating itself! There’s going to be a great cataclysm that knocks society back a thousand years!” The PCs leave very suspicious and confident that the Black Ships are not to be trusted.
Angering many of the city’s merchant powers attracts attention, and the next day the PCs are grabbed by the High Steward’s men. High Steward Piter de Vries (my rule is to only steal from things my players haven’t read or read so long ago they’ll never remember) offers them an alternative to being murdered in the present tense: Go and put down an assassin’s guild that’s not complying with city regulations, because if the Sisterhood (the kingdom’s bene-gesserit inspired priestess/assassins) get around to doing something about it there could be splash damage.
The Party investigates, picks out a merchant who probably hired the newcomer assassins, and ambush him at his house, then force him to arrange a meeting. When he explains that there’s never a real ‘meeting’ just a dead drop of money and a name, they have him do that, and then wait for someone to claim the money. It’s a close thing, but their thief manages to stay hidden and observe the assassin and trail him home. Upon confrontation, it’s…
Has’skein, the assassin with some of Magnar’s blood! What a twist! They’re all surprised and cheerful to see each other again because he’s a very friendly murderer. Has’skein is also surprised to see Magnar because he wasn’t expecting to visit for another month- it’s revealed he is the specialist that will deal with the elf problem! The party’s suspicions that torture will be involved multiply tenfold. They tell him to hold off another month before visiting because they’ll be out running errands.
With an opinion on the Black Ships and a mayor who has promised not to murder them in the short term, they find a wizard who is willing to reincarnate Garret as not a giant bird. He agrees, but only on the condition that he gets to cast Disintegrate on him, because he never gets to cast that spell. The party agree before Garret can react.