A Dance with Death

 is a faction quest in.

Synopsis
The only way to Ukaizo for the Principi starts by gaining command of Lucia Rivan's Floating Hangman. With the Engoliero do Espirs the Watcher is supposed to sail to sea and draw the undead Darcozzi paladin.

Lucia Rivan became a Death Guard because of her undying devotion to an oath she took to protect the Engoliero do Espirs. Aeldys discovered that speaking the dying oath of the Darcozzi while wielding the sword activates an aura which acts as a beacon for Rivan.

Walkthrough

 * Talk to whoever won the power struggle to become pirate leader in Honor Among Thieves. Your job is now to steal a ghost ship - the Floating Hangman, more properly named the Fonferrus - in order to be able to sail it to Ukaizo.
 * The only way to draw Rivan out into the open is by speaking the Darcozzi oath before her old sword, Engoliero do Espirs. The sword is currently guarded by Yseyr the Berathian in The Hanging Sepulchers beneath the Sacred Stair in Neketaka. To take it peacefully, you need to be a death godlike, have Perception 20, Religion 8 or you can simply pick pocket it from him, even if he is encountered earlier/before the quest (it will be a Quest item only at that point).
 * Sail away from the city, stand on your ship's deck, right-click on the Engoliero do Espirs quest item, and select "Speak the Oath". You are promptly boarded by Lucia Rivan and her undead horde. Unless you are able to pass a Diplomacy +17, Bluff +16 or Metaphysics +15 check, you'll have to smash her and her crew to bits to seize her ship. (If you just hand over the sword, the quest fails unceremoniously.)


 * Return to Dunnage to speak with the pirate leader to complete the quest and seal your alliance with the pirates. This will cause all other faction alliance quests to fail.
 * Alternatively, you can also just keep your spooky new ship (it's a galleon in terms of mechanics) and sail off, either to look for other allies, or to Ukaizo on your own. This will not align you with the Príncipi for the final confrontation at Ukaizo.
 * You can also kill whomever you left in charge of the council instead of turning in the quest, if you wish to keep the Hangman but aren't keen on having these particular pirates roaming the Deadfire. This will, of course, result in A Dance with Death failing, but you're left with a new ship and free to seek out other allies. (Attack via tool bar.)
 * Announcing your recently acquired captaincy of the Fonferrus will update the quest, having the Príncipi awaiting your signal to take their fleet into Ondra's Mortar. The Coming Storm will be completed, and you will start The City Lost to Time.
 * Note: unlike other faction quests, you wont get achievement for completion of principi quest line untill after reaching ukaizo

Consequences

 * Completing this quest will align you with the Príncipi for the final confrontation at Ukaizo.
 * After you meet with the Príncipi leader the last time, Pallegina will leave via a letter.
 * Speaking with Maia Rua after completing this quest will result in her leaving your company.
 * However, if you are in a relationship with Maia, you can convince her to stay by telling her "Stay with me. Fonferrus needs you and I do as well."
 * If you are successful and convince her to stay, Maia will leave the navy in her end-game slides.