Lexiconary

[barry921]

how do you get the stones to line up

[Belligero]

Are you talking about The Crossing puzzle?

First, activate the Stones by using the pressure plates.

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Drop an item through the gratings on both side. This will reveal a third pressure plate across the room which you must use the two activated Stones to throw an item onto.

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Line the two Stones to the right of the extended bridge to throw an item onto the pressure plate. This activates the third Philosopher's Stone.

Rest is self-explanatory.

If you still need help, just refer to a solution video.