Baldur’s Gate 3 has 3 acts to it. As you wrap up the events of an Act. you check off a significant milestone for the story. Each of these acts has plenty of side quests for you to explore and gain some extra experience.
Rescue the Grand Duke is a side quest you will be able to pick up and will not take you that long to complete if you know where to go and make a great time in the process.
Updated by Chad Thesen on August 17, 2023: This guide has been updated to feature new embedded links that can allow easier navigation for readers. These embedded links include one for a guide about how to complete a quest for Rugan, and the other being a link for a guide about building a Druid character.
Finding The Warehouse Basement
You will acquire this quest while on The Risen Road from Rugan. Once you have the quest, you can head on straight to rescuing the Duke. To do this, head on over to the Lower City location at X: -70, Y: -150. This will bring you to the docks, and some really large metal doors. You can brute force your way through, arousing suspicion in the processes, or be more tactful and pick the locks. Whichever you choose, be sure to have your frontliners ready at the doors. Opening these doors will reveal a pack of worgs inside. This will initiate combat.
Have your frontliners act as a barrier between the worgs and the doors to keep your back row safe. If you have a spell caster with powerful AoE spells at their disposal, have your frontliners just shy of the blast zone. This can deal damage to your enemies and coat the area while they fight your frontliners who are safe. Some good frontliner choices are Paladins and Fighters, as well as a Circle of the Moon Druid that can Combat Wild Shape. Some great back-row options are Rangers, Rogues, Sorcerers, and Wizards for their ranged DPS potential. After all the worgs have been dispatched, look at the North-West top of the warehouse to find a hatch that serves as an entrance to the basement. Interact with this hatch to travel through it.
Gain Access To The Submersible
Head all the way south through the area until you come to some large doors that say, “Machine Parts Storage.” Push these doors open, and you will come to a room with only one other way out. Moving your cursor over the other set of doors in the room will say “Subaquatic docks”. These doors can be found at X: -1068, Y: 307 in case you made a wrong turn. The doors lead into a room with lots of water and a metal bridge. Head East along the metal bridge and you will see Redhammer the Deviser. If you can take a long rest, do so, you will need it for what is to come.
Interact with Redhammer to update your journal and begin a dialogue exchange. You will need to convince Redhammer to let you use the submersible. You can do so by using your choice of Persuade or Intimidate. It’s not a bad idea to make a save before starting this dialog. Sometimes the dice rolls are against you and being able to take another crack at it is not something you should be afraid of doing. You have every right to enjoy the game and not feel obligated to use the results you got on the first try.
Freeing The Grand Duke
This will trigger a cutscene where you will delve into the depths inside the submersible vehicle. This cutscene will be cut short by some dialog from Lord Enver Gortash. After this exchange, you can leave the submersible and make your way to rescue Duke Ulder Ravengard. Defeat all the hostiles preventing you from progressing and make your way to X: 30, Y: 54. Mizora will manifest as you do. After some dialogue, make your way back to the surface and set up camp. Interact with the Duke.
Your best dialog option would be to use the parasite. This will allow the Grand Duke to see memories of the player character and that of Wyll. It will easily allow him to understand the reasoning for Wyll's actions and come to accept everything he has done. He will seek his son’s forgiveness and all the hostility and tension in his interactions will be no more. After this, you will receive a heavy amount of new information and lore. This will also set in motion a new part of your journey, and a new goal to set your sights on. You will be rewarded with a book titled, “The Legend of Ansur”, receive some journal updates and The Grand Duke quest will be marked as completed. Read the book you received for some more updates to your Journal.