Custom world generation/surface rule

** : Type of the surface rule, one of: bandlands, block, condition, or sequence. See below of extra fields for each type.
**; If is bandlands (used in badlands), no extra fields.
**; If is blocks (places the specified block), extra fields are as follows:
** : The block to use.
*** 
**; If is sequence (attempts to apply surface rules in order, and only the first successful surface rule is applied), extra fields are as follows:
** : (Required, but can be empty) List of surface rules.
*** : A surface rule.
**** 
**; If is condition (applies surface rules if the condition is met), extra fields are as follows:
** : A surface rule condition.
*** 
** : A surface rule.
*** 
Category:Java Edition
Category:Data packs
ja:カスタムワールド生成/surface rule
zh:自定义世界生成/surface rule