The party has returned from the abyss.
At least most of them have. After fighting through legions of abyssal hordes in the “hold” of the demonwing, the party finally fought their way to a large black massive orb floating in a room at the far end of the ship.
The Half-orc, the captain, and the alchemist all touched the dark-matter sphere, instantly disappearing. It took the ingenuity of the rogue and the monk to discover a positive matter analog to be used on the sphere itself to grant passage.
Upon placing the smaller orb against the larger orb, a portal opened up and a vast ocean of emptiness awaited them. The two adventurers entered the portal and could see constellations of stars in the images of their missing companions. Willing themselves over to each constellation, the power of the sphere was able to bring everyone back to prime material…except for captain Darius.
Unfortunately Darius had his life-force sucked out of his husk of a body and transmuted into a gem. A flickering hint of the captain can be seen within the gem when it is peered into intently.
The party only had to fight a massive chained demon, interact with some strange extra-planar beings on the ship, including a Githyanki from somewhere (or somewhen) else. And the party discovered an abyssal forge that had turned out magical abysmally enchanted weapons. The party had a close encounter with a couple of Vrocks as well.
After reaching the far end of the portal with the orb, the party landed on the deck of the demonwing as it hurtled along the river Styx. An ensuing battle with the current Glabrezu captain of the ship left the party battered and broken, but ultimately alive (save for the soul-trapped captain Darius) Having conquered the ship’s captain, the intrepid pirates took command of the ship and hurtled off of a massive waterfall, only to land smack-dab on the fever Sea in the Shackles.