Author: Lucas "Treeble"
This walkthrough was written by the author himself.
NOTE: there are two levels in the package, but it's actually one single level shared by two different characters. The level itself is pretty much the same, with only a few modifications in the beginning of the level, which are marked in Italic on this walkthrough. Have fun!
Playing as Lara, you start the level outside the VCI building. A flyby will show you the long climbing you will have to do in order to invade the building through the broken glasses. There's nothing outside except the van and the plants.
Once inside, run through the hall and activate the button. You'll find yourself in a familiar place - yes, Sophia's office. It seems someone escaped and left the exit door opened! Get the medipack by the chair near the windows and crawl through the ventilation tunnels behind the plant. An useless flyby will play to show you the place where you are.
(Playing as Sophia, you will start insider her own office and will need to push a button to open the exit door)
Do a long jump to the ledge on the opposite building and crawl through another ventilation tunnel. You get SECRET #1 here (a golden rose plus the HK Gun). Do a long jump back and hold action so Lara will fall in the ledge she came from. Crawl back to the office.
(Instead of the HK Gun, Sophia finds the Revolver as SECRET #1)
Going through the exit door, Lara will look upward and spot a tunnel above. Keep going and climb onto the two structures outside. From there, you can shimmy around the building until you come to the end, where Lara can put her feet onto the wall. Backflip and grab the wall, climb up to the small tunnel to get SECRET #2 (a golden rose and a flare supply). Drop to the outside and jump to the next building from the ramp to the extreme left.
Enter this new ventilation tunnel and go upward the ramp. Jump the hole on the floor and turn around. Jump backward and grab the above edge. Climb up to find SECRET #3 (a golden rose). Hold Lara on the edge again, drop and press action immediatly so she will grab the lower edge and jump the hole again. Slide down into the aquarium hall.
In one side of the aquarium there's a button - press it to open the door. As you enter, find a switch to your right. It will open another door in the aquarium hall where you will get a small medipack and a hidden map on the door. Once inside, press the look key to view the map.
Crawl through the new ventilation tunnels behind the plant. Climb up and go forward, in direction of a small yellow light you see ahead. There you can pick up SECRET #4 (a golden rose). Go back and crawl through the darkness to climb down into another office room. If you look through the windows you'll see that a guard and a dog are looking for the intruder spotted by the camera on the wall.
Push the button and go into this building's hall. Go to the first door on the North wall and kill the two guards. You'll soon find yourself in a white board room. Remember the map you saw in the aquarium room? But first, activate the button switch on the left wall to open the door. You can step only in the tiles that were marked in the map by the aquarium room, otherwise, Lara will burn.
Once you make your way through it, you will find the Isis' Eye protected by four guards. Kill them and pickup the relic. Activate the switch and go back to this building hall (yes, through the white board). Kill the two guards and go outside the broken window. Wait until the helicopter appears and jump for the finish.