What Lies Dreaming is the fourth main mission in the first story DLC for Borderlands 4, Mad Ellie and Vault of the Damned.

The core of this mission is entering Vault of the Damned deep within Whispering Glacier. The process includes exploring a destroyed ship, restoring power, and dealing with ambushes. Upon completion, you will receive experience points, Borderlands 4 Money, Eridium, and a green or blue assault rifle.

The mission is divided into four stages. This guide will walk you through each step of What Lies Dreaming, providing a detailed completion walkthrough:

• 1. Reach Storm
• 2. Reach Ship
• 3. Reach Engine Room
• 4. Defeat Colonel Crash

1. Reach Storm

The core of this stage is reaching the red storm area in Maelstrom. To get there, you need to traverse a snow-covered wasteland, following the marker at the top of the screen. As you get closer to the red storm area, you'll realize that direct entry is not possible.

At this point, Captain Willis's voice will appear in the communication, warning you not to proceed. You then need to change direction and follow the red spiked passage on the right side of the storm to the stern of a crashed ship. One end of the ship is embedded in the storm, forming a natural passageway inside.

After passing through the passage, you will see the wreckage of a ship. One end of the ship is inside the storm, and the other end is outside, so you can enter the storm via the ship.

There are multiple routes to the ship, some faster, but the core objective is to reach the stern at the bottom of the map. As you approach the ship, you will see a long bridge; simply cross it to board the ship.

2. Reach Ship

While crossing the long bridge leading to the ship, you will encounter a large Thresh O' War, which deals Cryo damage and has two health bars. It is recommended to use Borderlands 4 Items with Corrosive attribute and high-explosive homing missiles to deal with it, such as Darkbeast, Disc Jockey, and Swarm.

After eliminating the enemies, enter the ship's entrance and find Ellie. Help her eliminate the five surrounding enemies, then talk to Ellie. Scan the three green-glowing weak points on the ship's hull (the third is in a hole in the side wall). Locate them and destroy the vent to enter.

Turn to face the ship and approach the most damaged area on the side of the hull. As you approach the hatch, a prompt will appear. Once ready, press the button displayed on the screen to begin scanning - the specific button depends on your controller.

After scanning the first weak point, turn right to scan the next one; then move left along the hull to scan the last weak point. Unlike the first two, this weak point is not on the outside of the hull, but hidden in a large cave on the side.

Enter the cave and scan the vent to find the entrance. Quickly destroy the vent to enter the cargo hold. Use the grappling hook on the central mechanical device in the cargo hold to climb to the upper level. Defeat the enemies lurking on the upper level, then use the control panel to try to open the cargo door.

Unfortunately, there's no power available right now. Turn around and find the circuit breaker - it's located in the cargo hold control room.

The control room is on the south edge of the cargo hold. To enter, go up the stairs on the left side of the control room and pull the handle on the control panel on the wall to activate the first breaker. The second circuit breaker is near the computer in the corner of the room.

Once power is restored, you can enter the upper control room. Have Ellie go in with you and eliminate the enemies that have been attracted there.

You and Ellie are successfully reunited, and the enemies are defeated. Follow her to the control room in the center of the room. After reviewing the ship's blueprints, Ellie sets a plan: the first step is to find the cryogenic storage area.

Climb the collapsed pillar on the right side of the control room to reach the upper level, then follow Ellie to the elevator - but the elevator is out of power.

Fortunately, you're already an expert at restoring power. There's a power core on the other side of the room. To get it, you need to use the robotic arms that span the room - the storage boxes they're holding form a makeshift bridge.

Cross the bridge to retrieve the core, return to the elevator to install it, and then protect Ellie from enemy attacks while she adjusts the control panel. After clearing the enemies, the elevator is finally usable.

Take the elevator up and follow Ellie into the cryogenic chamber room. Give her the Keystone Fragment obtained from defeating Crazy Earl. Hold onto the handrail and enter the illusion.

3. Reach Engine Room

When you return to reality, Ellie is gone. You need to search for her in the corridor and collect as much loot as possible to prepare for the upcoming battle. Once you notice strange organic matter appearing on the ship's hull, you're on the right track.

Continue forward to find the vent, break it, and crawl into the passage. Follow the mission marker to a room, jump down, and clear enemies along the corridor.

Finally, you'll encounter a door that requires the energy core to open. Turn around and enter the opposite dormitory. Climb through the small hole on the right to retrieve the core, then return to the entrance to activate the door. After passing through the door, climb the ladder in the center of the room, enter the vent again, sneak into the next room, and follow the corridor to the engine room.

The engine room is teeming with enemies. First, take out the regular Dahl soldiers, then deal with the large man in saturated protective suits. He's heavily armored, his health bar is yellow-blue, and his defenses can be easily broken with corrosive and electric damage. After defeating Dahl, Ellie will contact you via communicator; she's safe and sound, so you can continue.

The next objective is the main control room to activate the switch and engine overdrive. Follow the marker to the control panel in the center of the room. After completing the first step, you'll still need a keycard. Turn right with your back to the control panel, find another vent, break it, and jump down to enter another room full of enemies.

After clearing the enemies, follow the marker to a narrow platform above red liquid. The keycard is on the left beam. Pick it up, climb the stairs on the right, then climb the ladder back to the main room. Insert the keycard into the control panel to activate the engine overdrive.

Turn around and use the grappling hook to retrieve the spark plug above, then turn around again and use the grappling hook to start the engine on the ceiling.

Once the engine is running, go to the other side of the room and pull the control panel lever to unlock the path ahead. Head to the newly opened door in the rear right corner and begin searching for Ellie. You'll encounter enemies along the way and then return to the outside of the ship. Jump over the metal platform and crawl into the cabin through another hole on the side of the hull.

Turn right, and you'll see Ellie on the other side, but the gap is too wide to jump across. Look to the lower right - there's a pile of rubble. Break it to get a speed booster. Scan the speed booster to learn its function, then follow the yellow cable extending from it to find and destroy the power regulator. Next, pull the lever on the left side of the room to activate the jump pad. Finally, use the jump pad on the right to leap across to the other side.

Find Ellie in the ship's corridor and go through the door she opened. There are two vending machines on the right side of the room. Jump down through the hole at the back of the room and follow Ellie to the operations room. Someone is waiting for you there: Colonel Crash.

4. Defeat Colonel Crash

Colonel Crash is the final boss of Borderlands 4 What Lies Dreaming Quest, possessing two health bars: blue and red. Prioritize blue targets and use electric damage to counter them; after defeating the boss, only the red health bar will remain, which can be dealt with using burning damage. It's best to prepare both types of damage.

During the fight, be aware of the following attacks: The long-range red laser will first shoot towards the back of the room, then sweep twice horizontally; you can avoid this by hiding behind control panels. Afterward, he will summon multiple stationary lasers to restrict movement.

The boss will teleport and leap, disappearing as a red ball, reappearing about a second later and causing a purple explosion that deals extremely high damage. He can also summon some floating heads that will disappear on their own after a while; it's recommended to focus on dodging these and attacking the boss. His flamethrower has a small range; maintaining distance will prevent damage.

Your advantage lies in the control panels around the room - use them wisely as cover, otherwise they will hinder your movement; make sure to turn disadvantages into advantages.

After completely defeating Colonel Crash, take the keycard and meet up with Ellie. Open the door, listen to Moxxi scold Ellie, and then enter the bridge. Continue onward to find Moxxi and retrieve the Echo Log from a corpse covered in organic matter. Finally, pull the lever to blast open the breaching door and reveal the vortex.

This completes the What Lies Dreaming quest. After completing the quest, keep an eye out for the unlocked side quest, Summoner's Gift, which can be accepted from Belle in the Crooked Teeth area. The reward is a green or blue rarity SMG and a Vault Hunter head skin.

Hopefully, this guide will help you easily complete Borderlands 4 What Lies Dreaming quest and claim your rewards.