The Midgard Serpent - Razor House Key (and Treasure #42)

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To get past the series of spear and blade traps, start near the middle of the room a few steps back from the first set of spears. When they retract, run forward past the groove where they emerge from the floor.

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Once you've cleared the groove, immediately stop moving forward and crouch. At this point, a situational adrenaline sequence begins and a set of slicing blades whips back and forth above Lara's head. The camera shifts to one side, making it difficult to maneuver, but it's OK. As long as you stay low, there's no need to move at all. The blades won't touch Lara.

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When the blades stop moving, you'll have control of the camera again, and you can stand up and walk forward toward the second set of spears.

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When they go up, run under them, stop and crouch again. As time slows and a second set of blades does the slice-and-dice thing above Lara's head, just stay still and low.

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When the blades stop moving, stand up, walk around them and approach the third set of spears. Wait for them to retract and run through. Take the health potion in the right corner and the RAZOR HOUSE KEY from the pedestal.

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To get out, and get a treasure in the process, turn around to face the entrance and go to the right wall. Climb the rocks from bottom right to top left. Then jump over the spears to land on top of the nearest inverted blade. If you don't want the treasure, just drop to the floor and head for the exit.

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To reach the treasure, you must hop across the tops of the blades. Walk to the end of the first blade and jump to the second. Jump from this blade to grab the third. Pull up and then jump to the fourth blade.

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From there, you can jump to grab the alcove above the entrance, where you'll find a treasure (42/50). When you have it, hang from the edge and drop to the floor.

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