Mission 4 — Regina: Underwater 3rd Energy Reactor

Control returns to Regina aboard the docked Patrol Ship. Access the EPS terminal to purchase the Heavy Machine Gun (essential for rapid takedowns):

• Walk onto the dock walkways. Eliminate surfacing Plesiosaurs with single bursts of machine gun fire.
• In the Storage Space corner where the truck has crashed, collect Dino File 5 (Pteranodon).
• Swipe the 3rd Energy Facility Keycard at the card reader beside the brown door.
• Advance past the small boat containing a locked glowing box and enter the 3rd Energy Control Room.
• In the control room, pick up Dino File 6 (Mosasaurus) from the central table and take the Key for the Box from the upper desk.

• Pass through the control room's rear door to reach the storage bridge and search the fallen technician to obtain the Mechanic's ID Card.
• Backtrack to the small boat at the docks and unlock the glowing box using the Key for the Box to reveal a document containing an access passcode (this code is randomized per playthrough).
• Return to the elevator in the 3rd Energy Control Room: swipe the Mechanic's ID Card and enter your specific passcode.
• Ride the elevator down to the flooded sub-level and enter the generator chamber:
  • Interact with the power restoration monitor and select Yes.
  • Watch the wall panels: whenever a lamp turns red, immediately strike it with the Stungun to turn it green.
  • Continue maintaining the circuits for approximately two minutes until primary power stabilizes.
• Climb the platform ladder to the suit locker and inspect the center locker to acquire the Diving Suit.

Subsea mechanics take effect: movement is slowed, jump is bound to the jump button, and loadout switches to the Needle Gun (infinite ammo) and Shockwave:

• Eliminate the two Mosasaurs and jump down through the underwater corridor to reach the safe room.
• Access the EPS computer and purchase the Aquagrenade (mandatory torpedo weapon).
• Advance through the lower chambers, clearing Mosasaurs along the ocean floor.
• Approach the elevated platform supported by a cracked pillar: fire an Aquagrenade to demolish the pillar and jump up to the upper door.
• Pull the wall lever inside to activate the elevator lift.
• Cross the pipe bridge, drop onto the lower platform, and inspect the deceased diver to retrieve the Reactor Plug.
• Return to the first save room, insert the Plug into the central computer, and select Yes to open the 3rd Energy Reactor shutters (collect Dino File 7: Plesiosaurus beside the corpse).

• Head through the lower double doors, jump over the partially opened security shutter, and ride the small red elevator up to the 2nd floor.
• Cross the upper bridge, jump down into the south trench, and enter the final underwater save room.
• Ensure you have at least 6 Aquagrenade torpedoes loaded.
• Take the red elevator, leap over the open reactor barrier, and collect the City's Keycard lying beside the corpse ahead.
• Ride the adjacent elevator down into the central reactor arena.

• A massive Plesiosaurus blocks the reactor exit passage:

• Scale the reactor platforms, activate the elevator console, and ascend to the surface.
• At the Edward City Front Gate, Regina meets Dylan and unlocks the perimeter gate with the City Keycard. A transmission from David urges the team into the city!