Vault Keycards

Test Chamber 13: Place portals as shown in the image. Use one portal to move the laser sideways and a time portal to send it into the future. You can take some damage from the laser to travel into the future. Once in the future, rearrange the portals so the laser goes directly into the target.

Test Chamber 14: First, take a time portal to the present. Summon a reflector cube from the center switch and position it as shown. Use a portal to bring a laser through the first node, then use the reflector cube to direct the laser into the next two nodes. Travel to the future. Use portals to bring a laser into the present through the time portal, ensuring it goes through the node. Retrieve the reflector cube from the future and bring it to the present. Position the present reflector cube to hit all three nodes. Travel back to the future to retrieve the future reflector cube and bring it to the present. Place this cube at the end of the nodes to reflect the laser into the receiver.

Test Chamber 15: Go 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. Return to the present using another time portal to be on the other side of the field. Place a new portal on the upper wall so the laser hits the first receiver. Travel to the future and place a portal on the small wall in the laser room to shoot the receiver. Return to the present; the laser should power up an elevating platform. Stand on it and place a time portal behind the node to raise the platform, allowing you to summon a reflector cube. Place this cube on the lip above the second receiver. Travel to the future. Retrieve the future reflector cube and bring it to the present by placing a time portal in the laser room. Position the cube to reflect the laser into the second receiver through the node. To get to the other side of the particle field without going through it, use a portal on the other side or a time portal. Once in the present on the other side, climb the stairs and use a portal on the upper wall to hit the third receiver. Finally, move the reflector cube onto the switch to complete the chamber.