How to Beat Hakar

Test Chamber 13: Place portals as shown to move the laser sideways. Use a time portal to send the laser into the future. Travel through the time portal (taking damage is acceptable). Rearrange portals in the future to direct the laser into the target and exit the chamber.

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 and 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 passes through the node. Retrieve the reflector cube from the future and bring it to the present via a time portal. Ensure the present reflector cube hits all three nodes, adjusting as necessary. Travel back to the future to retrieve the future reflector cube if needed. Place 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 the future to bypass 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 direct the laser to the first receiver. Travel to the future and place a portal on the small wall in the laser room to aim at the receiver. Return to the present. An elevating platform will power up near the switch. Stand on it and shoot a time portal behind the node to raise the platform further, allowing you to summon a reflector cube. Place this reflector cube on the lip above the second receiver. Travel to the future. Retrieve the future reflector cube and bring it back to the present via a time portal placed in the laser room, aiming it at the second receiver through the node. To reach the other side of the particle field without going through it, use an existing portal 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.