The scripting command AlterMap has the opcode (0x13).
- X-Coordinate (byte)
- Y-Coordinate (byte)
- Byte - Wall
- Byte - Value
Sets the wall value of the given X/Y coordinate of the current map. See MAZExxx.DAT File Format for further details on the map structure.
This is only ever seen on indoor maps, which use wall values. It should behave in a similar way on outdoor maps, using the 4 layers instead of 4 walls, but it's hard to be certain without an example. In some single maze maps, the X and/or Y values are incremented by 16 as if they were the second half of a multi maze map. See MAZE0054 (Witch Tower Level 4) for example. This seems superfluous and easily ignorable. Tests which set it back to the expected sub 16 value made no difference in the result.