Return to the greenhouse, go left, find the hatch and go down. Take the lab card (east) from the table in the corner. Go to the waiting room, follow it to the middle and find a few corpses. There is a trophy on the table, and on its back wall you can find the code for the terminal with strange characters. However, we have already entered the right combinations, so the trophy will be marked with a red tick.
Go through the far door, at the end of the corridor, kill two Lickers. You can just run away from them. Climb up the stairs, enter the room and find the modulator of signals on the left. Open another door to be in the lobby of the east wing.
Return to the bedroom where you found the electronic chip. There is a switch on the wall. Examine it and see the inscription MUF. Open the signal modulator in your inventory, switch to MUF (see above) and adjust the waves so that they are aligned with each other. After that, apply the tuned modulator to the switch in the wall, which will allow you to supply electricity. The shutters will open to the side, a zombie will fall out. Kill him and take the bag from the bed. If you find all the previous ones (a total of six), then increase your inventory to the maximum, getting an achievement.
Now go to the rest room, go down through the hatch of the greenhouse, then find the terminal with the inscription MURF. Set up a signal modulator in your inventory, aligning all the waves at the MURF frequency, and then apply. Due to this, electricity will appear in this wing. Log in to the server where you can save. After that, move to a low-temperature testing laboratory. On the way, read the message on the PC, and then apply the solution cartridge to the device. Cool it; you get a cartridge with a herbicide. Return to the control room of the conservatory and place this cartridge in the console to get rid of the undergrowth.
Go to the greenhouse and find the corpse in the right side, next to which lies the electronic chip. Combine it with an ID bracelet to get access to a senior employee. You can read the letter on the laptop on the way back to the meeting room.
Go back to the main shaft and use the terminal with a purple screen. Go to the west wing and pick up a video cassette near the corpse of a soldier. In the first room, there is an OSS terminal in the right corner. Adjust the signal modulator to the appropriate wave and apply to the terminal to turn on the light. After that, this device will no longer be needed.
Go deep into the wing and collect the tube with the G-virus. Go back, watch the videos, and then enter the elevator. Make your way past the opponents until the Tyrant stops you. In the end, you will find yourself in front of a large lift. Take everything you have. Very useful revolver and cartridges to it will be. Pick up the power element and place it in the lift control panel.
When you go down, the battle will begin against Tiran. Run away from him, shoot at the head. In the end, he will get angry, and two stones will fall on top. You can hide behind them from the Tiran. When the Tiran begins to get angry and shout loudly, then select a revolver and shoot several times in the head to interrupt his charged attack. You can avoid him on a light level of difficulty, but on a hard — it is impossible. Therefore, the only option is to shoot a revolver in the head.
In the end, the box with the rocket launcher will fall down below. Pick it up and destroy the monster. Take the only path until you reach the funicular. In this walkthrough of the game for Leon will be completed.