How to Beat Hotep

Test Chamber 13: Place portals as shown to redirect the laser. Use a time portal to move the laser into the future. Run through the time portal (taking damage is okay). In the future, rearrange portals to direct the laser into the target.

Test Chamber 14: Travel to the present via a time portal. Summon a reflector cube and position it as shown. Use a portal to bring a laser through the first node, then use the cube to reflect it into the next two nodes. Travel to the future. Use portals to bring a laser into the present through the time portal, ensuring it hits 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. If needed, return to the future to retrieve the future reflector cube again. Finally, place the future reflector cube 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. Head to the other side of the room and use another time portal to return to the present, now on the other side of the particle field. Place a new portal on the upper wall above the laser room to hit the first receiver. Travel back to the future. Place a portal on the small wall in the laser room to shoot the second receiver. Return to the present. An elevating platform near the switch will power up. Stand on it and place a time portal behind the node to raise the platform further. Summon a reflector cube and place it on the lip above the second receiver. Travel to the future. Pick up the future reflector cube and bring it back to the present using a time portal in the laser room. Position it 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 an existing portal or a time portal. Once on the other side in the present, climb the stairs and use a portal on the upper wall to hit the third receiver. Move the reflector cube onto the switch to complete the chamber.