Find The GEU Droid

Test Chamber 13: Place portals as shown in the image. Use a portal to move the laser sideways and a time portal to send it into the future. You can take some laser damage to travel to the future. Once in the future, rearrange portals without affecting the present. Aim the laser directly into the target to open the exit door.

Test Chamber 14: First, travel to the present using a time portal. Summon a reflector cube from the central switch and position it as shown. Use a portal to direct a laser through the first node, then use the reflector cube to guide it through the next two nodes. Travel to the future. Use portals to bring a laser into the present through the time portal, ensuring it passes through the node. Retrieve the reflector cube from the future and bring it to the present via a time portal. Adjust the present reflector cube to hit all three nodes. If necessary, return to the future to retrieve the future reflector cube again. Finally, position the future reflector cube to reflect the laser into the receiver, completing the chamber.

Test Chamber 15: Start by going through the particle field to the left. Place a portal where the laser hits the wall and a time portal on the opposite wall. Travel through the time portal to reach the future, bypassing the particle field. Head to the other side of the room and use another time portal to return to the present, now on the far side of the particle field. Place a new portal on the upper wall above the laser room so the laser hits the first receiver. Travel back to the future and place a portal on the small wall in the laser room to aim at the receiver. Return to the present. The laser should now power up an elevating platform near the switch. Stand on the platform and place a time portal behind the node to raise the platform further, allowing you to summon a reflector cube. Place this future reflector cube on the small lip above the second receiver. Travel to the future. Pick up the future reflector cube and enter the laser room. Use a time portal in the laser room to bring the future reflector cube to the present, positioning it to reflect the laser into the second receiver through the node. Now, reach the other side of the particle field without passing through it. Use an existing portal or a time portal to get to the present on the other side. Climb the stairs and place a portal on the upper wall to hit the third receiver. Finally, move the reflector cube onto the switch to complete the test chamber.