So, you want to drain the Reservoir in Blue Prince? This area is found in a massive cavern and, if it's your first time discovering it, you just know that something's down below. While you might already have an idea of what to do, things can get a bit complicated once you're back inside the manor. In any case, we want to remind you that this guide contains spoilers.
How to drain the Reservoir in Blue Prince
The Reservoir is a huge area found in the Underground. It's what separates the two halves--i.e. west (Fountain entrance) and east (Foundation entrance).
You can fully drain the Reservoir by using the controls in the Pump Room. The process is akin to what you did for the Fountain. But there's a big difference this time:
- Remember: You have to draft a Pool first just to make the Pump Room appear as a drafting option.
- The Reservoir has 14 water levels. Just like math, you can think of this as +14, and we have to bring it all the way down to zero.
- The Pump Room's main tanks, by default, cannot hold that much water. You need to use the reserve tank, which can only be powered up via the Boiler Room.
How to activate the reserve tank in the Pump Room
Thus begins the most convoluted step if you want to drain the Reservoir in Blue Prince. Basically, you must have a Boiler Room drafted in the house. Once you've activated it, you must ensure that power can be funneled to the Pump Room.
- There must be an unbroken connection/pathway between the Boiler Room's openings and the Pump Room's openings.
- You can form this path via gear-type rooms with doorways (i.e. Security, Workshop, and others), or via red rooms (i.e. Gymnasium, Archives, and others). You'll notice that these rooms have ducts/shafts that lead to a location.
- Make sure the Boiler Room's control panel slider is pointing toward the direction of the shafts/ducts leading to where the Pump Room is located.
- Alternatively, you can make use of the Aquarium as long as it has the Electric Eel upgrade. This also acts like an activated Boiler Room.
