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The element puzzle was used in the TR4 The Mastabas level. It contains 3 scales where you have to place the elements water, fire and earth, for the next door to open.
The puzzle is made using 4 ELEMENT_PUZZLE objects and 4 HEAVYSWITCH triggers. First of all, place 1 ELEMENT_PUZZLE with OCB 3 somewhere in the room. It will be invisible, so you can put it anywhere. Below this object, put a HEAVYSWITCH trigger for the door you want to be triggered when the puzzle is completed. This is the dummy element puzzle, with a hardcoded effect.
 Water element
For the water element puzzle, put 0 in the OCB of the ELEMENT_PUZZLE. Also enable the first codebit in the OCB. Below it, put a HEAVYSWITCH trigger for the OCB 3 element puzzle. In the trigger, check the first codebit and uncheck the rest.
 Fire element
For the fire element, put 1 in the OCB of the ELEMENT_PUZZLE. Also enable the second codebit in the OCB. Below it, put a HEAVYSWITCH for the dummy element puzzle with again the second codebit checked and the rest unchecked. Also make sure the PICKUP2 object is defined correctly in the script:
- Pickup=2,Jerrycan, $0015,$0500,$4000,$f000,$0000,$4002
 Earth element
For the earth element, put 2 in the OCB of the ELEMENT_PUZZLE and check the codebit buttons 3, 4 and 5. In the HEAVYSWITCH trigger below it (again for the dummy element puzzle), also check the codebits 3, 4 and 5 and uncheck 1 and 2. In the script define the PICKUP1 object:
- Pickup=1,Bag of Sand, $0000,$0400,$0000,$2000,$1000,$8002
To solve the object, there has to be some elements available.
To insert water Lara needs a filled WATERSKIN. The waterskin must be available in the level, as well as water where she can fill it.
For the fire puzzle, Lara needs a jerrycan with fuel, and a burning torch. The jerrycan is in the PICKUP2 slot. The torch is the BURNING_TORCH item, which must be lit using a flame before it can be used. Make sure Lara can get and light the torch in this room.
To insert earth Lara has to use the bag of sand object, which is located in the PICKUP1 slot.