It's a Madhouse! - Overgrown Area with Spiked Walkways

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Exit the room where you obtain the FIRST AVIARY KEY through the doorway opposite the entrance.

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Inside this room, turn right and walk carefully to end of the broad branch. It's a long way down and there are spikes below. If you have ammo to spare, you can use the MP5 to shoot the white tiger below.

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Jump straight up to grab the branches on the ceiling.

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Monkey swing forward...

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...a little to the left, then forward some more toward the far end of the room.

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When you reach the thick vine hanging from the ceiling, turn right...

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...swing forward as far as you can, then let go...

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...and immediately press Jump + Action to leap forward and grab the horizontal crevice on the wall. Traverse to the right along the crevice as far as you can.

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Then drop to land in a safe spot amid the spikes. Kill the tiger if you didn't do it before.

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