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Part 21
Portal: Revolution

Part 21

Complete the Part 21 challenges in Portal: Revolution, including Lemmings Four the Drop, Booby trap, and Hit 'n' Run.

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Complete the Part 21 challenges in Portal: Revolution, including Lemmings Four the Drop, Booby trap, and Hit 'n' Run.

Walkthrough
  1. 1
    Have a climber dig to the right. When they reach the pit, have them build to the wall. They will turn around and reach the balloon.
  2. 2
    Turn the level and go to the next one on the right. Have this Lemming dig left, then build ONE bridge up to the next pylon to the left.
  3. 3
    Activate the lever to supply metal ground for the Lemming on the far right to fall to when you dig them out.
  4. 4
    Once the second Lemming turns the lever, the floor will open, and they will head to the balloon.
  5. 5
    Assign the third Lemming an umbrella and make them dig out of their cubby hole while facing right.
  6. 6
    Build two bridges up to the metal floor for the floater.
  7. 7
    When the floater hits the metal floor, have them build the rest of the way to the exit.
  8. 8
    Free the last Lemming by making them dig when they face left.

056. Booby trap.

Walkthrough
  1. 1
    Have the first Lemming become a climber and set the release rate to 99.
  2. 2
    Have the climber bash the thin wall to fall into an area with a switch.
  3. 3
    Wait for the climber to walk to the small alcove to the right, then build into the wall for a quick turnaround.
  4. 4
    The climber will turn the switch, opening the metal door.
  5. 5
    Allow the remaining Lemmings to walk toward the portal and exit on the right.
Tips
  • This level relies heavily on luck and speed.
  • The climber may not survive to the bottom; focus on activating the switch.
  • A glitch may cause some Lemmings to not be sucked back into the portal, aiding in their survival.

057. Hit 'n' Run

Walkthrough
  1. 1
    Make the single Lemming falling from the right a blocker.
  2. 2
    Have one of the other Lemmings climb over the closed metal door.
  3. 3
    Ignore the Lemmings heading toward the laser detector as they are safe.
  4. 4
    Guide your climber up to the ceiling and toward another gravity pad that returns them to the ground.
  5. 5
    Direct the climber toward the deadly pool of yellow lava.
Tips
  • The laser detector has no significant purpose in this solution.
  • Be aware of the deadly yellow lava pool.

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