In the penultimate Chapter ofPortal: Revolution, the game-sizedPortal 2mod, you will be reunited with an old friend as both sides make their case. All the while, you’re forced to solve a range of new test chambers using the Quantum Cube. It can be powered by and used to redirect lasers.

The puzzles introduced in Chapter Seven aren’t as complicated as some of the ideas in Chapter Six, with most of the solutions being pretty understandable if you’ve been able to make it this far. Just think about how previous chapters have introduced new items, and you’ll likely see how you build off each new test.

A screenshot from Portal: Revolution showing the player character holding the Blue Personality Sphere while the orange one in the background can be seen on a TV screen. The orange sphere is speaking, with text subtitles reading ‘At least you didn’t suffocate in a wall, so that’s good."

Reunion

The Reunion largely consists of you getting off an elevator and watching a scene on the TV. When it’s over,go through the broken windowand take a right,shimmying along the wallnear the window.

Continue along the wall and thengo up the rail steps. Go through the door and continue walking until you have toput the Blue Personality Sphere on a rail.

A screenshot from Portal: Revolution showing the player character aiming a Prism Cube to redirect a laser

Shoot a portal through the broken glassand thenshoot another on the wall next to you. Go through andwait for the exit door to unlockto open the path to the elevator.

Quantum Cube Introduction

Go up the stairs andcontinue walking through two circular doors. In the test chamber,grab one of the Quantum Cubes and place it in front of the laserto power it.

Grab the other Quantum Cube andtake it to the other sideof the wall.Aim the laser at the receptacleto lower the walls andshoot a portal on both sidesof them.

A screenshot from Portal Revolution shooting blue gel through a portal to get sucked in by a vacuum tube after launched out of the other portal.

The Quantum Cube ispowered by direct output from a laser, meaning lasers reflected won’t work to power it.

Take the cube through andaim it at the input to open the exitdoor.

Go through and then through the next door toenter the next testing chamber. In the room,take a left through the energy field.

Shoot a portalon the wallin front of youandone by the Quantum Cube. Bring it through the portal andput it under the laser,aiming it at the inputon this side.

Go back through the energy field anduse the laser coming from the other Quantum Cube,andpoint it into the inputwhile stillunder the new laser.

This will create alaser output out of the other cubeas well, and if you already aimed it at the input, it shouldautomatically unlock the exit door. Use portals again to get across the water.

If you hold the Quantum Cube,it should correct itselfto where thelaser output is pointing away from you. Even when it’s not powered on, use this to aim ahead of time.

In the next chamber,drop and shoot one color portal at the end of the laser. Next, take the first Quantum Cube and put itbehind the first light sensor.

Next, shoot the other colorportal in front of the light sensorpowering your Quantum Cube.Aim that cube through the other light sensorand the elevator control.Move the second portaland thenput it back when you’re on the elevator.

Go through the door to the next chamber, grab the Prism Cube, andredirect the laser to the wall by the ‘04’ sign.

Shoot aportal where the laser pointsand the otherportal in front of the light sensorsso they’re powered on. Then, take one of theQuantum Cubesand put itat the end of the lightsensor path. Use the other Cube to power the exit door.

Go through andget on the elevatorto end this section.

Quantum Cube Reinforcement

Continue along the available path to enter the next test chamber. Once inside, take one of the Quantum Cubes andplace it under the laser,pointing its output at the sensor ahead of it.

Next, take the other Quantum Cube near theother sensor on the lower level and power it. After that,use portals to get backto where you started.

Goacross the light bridgeandstep on the launch padto move to the upper level.

Shoot aportal on one walland walk to the grated wall to shoot aportal near the second Quantum Cubeon the lowest level.

Go through, pick up the cube, and go back. Place the cubeunder the laser to power up the cube on the platformbelow.

If you aim it correctly,it should automatically power the exit doorand let you out.Get on the elevatorto end this section.

Quantum Cube Flings

Move along the available path until you get to alauncherthat will take youto a landing spot.

Once there, shoot aportal into the darkened spots in the wallsanduse the small buttonto release two Quantum Cubes.

Place oneunder the laserandone aiming through the lower portal, with the higher portal hitting the sensor.

Next, go near the launcher on the lower level andshoot a portal on both slanted walls. Step on the launcher to send yourself through both.

Once through the second portal, quicklyshoot one of each on the darkened areaswhere you lined up the Quantum Cubes.This will activate a platformyou can land on.

There aremere secondsto shoot the portals, so don’t feel bad if this takes multiple attempts.

On the second level,shoot a portal near youandnear the cube.

Go through,grab the cube, and thenuse the laser to destroy the line of turretsthrough the window. Then,aim it through the inputto power the exit door and leave. Get on the elevator to end the section.

Quantum Cube Examination

Go through the circular door and into the test chamber. Once inside,shoot a portal on the highest wallto your right and thenstep on the launcher.

Before you landon the middle platform,shoot the other colorso that you’re launched through. After you’ve landed, press the button andplace the second portal under the blue geldispenser.

The ticking meansit is a limited burst of blue gel, soyou may need to press the button twiceto coat the surface next to you.

After that,use two portals to return towhere you started.

Use the same method toget on the higher platformas you did before, only this time, you’llland on the goo and bounceacross the gap.

Take both Quantum Cubesanddrop them off the edgenear the laser.Place one Quantum Cube under the laserandaim the other through the sensorand into the input.

After both are activated, use a portal to get back to the starting area.

You will launch yourself like before, but shoot aportal on one of the sides of the high wallfirstso you don’t land on the bouncing gel.

Shoot aportal under the dispenserandone on the high wall near where you started. Press the button tosend gel throughand into the vacuum.

The blue gel willcoat the middle platform, making it bouncy. Next,pick up the Quantum Cubeandput it in the Vacuum Tube.

Return to the beginning using portals andstep on the launcher. This time, you’ll go through the tube and bounce on the middle platform.

If you try to go through with the cube, the physics will be off, andyou won’t bounce far enough, but the cube will.

On the other side,aim the cube at the inputto open the exit door. Follow the path onto the elevatorto finish this Chapter.