Custom world generation/block predicate


 * : The type of the block predicate. One of,  ,  ,  ,  ,  ,  ,  ,  ,  ,   or.
 * If  is   or  :
 * : The child predicates. If used with, all the childs need to pass. If used with  , at least one of the childs needs to pass.
 * If  is ,  ,  ,  ,  , or  :
 * : (optional) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
 * : Must be between -16 and 16 (inclusive).
 * If  is  :
 * : The direction of the block to check if it is sturdy. With sturdy is meant that the block needs to provide full solid support on that face.
 * If  is  :
 * : The block tag to check.
 * If  is  :
 * : The list of blocks that will match.
 * : A block ID
 * If  is  :
 * : The list of fluids that will match.
 * : A fluid ID
 * If  is  :
 * : The block predicate to invert.
 * If  is  :
 * : The block state to use when testing if it would survive in the current position.