Minecraft wiki entry for Caves_%26_Cliffs_Prototype_Data_Pack, associated text: The Caves & Cliffs Prototype Data Pack is an official data pack that was released periodically by Mojang Studios from April 2021 to May 2021.[1] It contains several experimental and work-in-progress features, most of which were eventually released in Java Edition 1.18. Its first release coincided with the announcement that Caves & Cliffs would be split into two major updates.[2][3] The data pack was eventually superseded by experimental snapshots as changes that are too large for a data pack were introduced.[4]