Gravity Duplication Return

Players once duplicated falling blocks by sending them through an End Portal while the source world was changing dimension. Later versions removed that behavior. This Fabric mod brings it back for server owners who want the mechanic available, and it runs on the server alone, so players join without installing anything. Fabric API is required.

The duplication can be tuned with two GameRules, one that allows the mechanic for entities in general and one that allows it for dragon eggs specifically. Server owners can keep sand duping available while leaving dragon eggs unique. Entity types can be added through a data pack tag named gravity-duplication-return:duplicatable, and falling blocks are included by default. Each duplication is written to the server console with the entity and the End Portal coordinates.

The mod also reverts a fix that stopped entities from passing through portals, so an entity that enters an End Portal stays in the source world after teleporting. The check uses a fast path for standard falling blocks, which keeps the server tick cost low even with high-speed duplication machines. Files target 26.1 – 26.2, and the 1.0.0 build for 26.2 was published on 2026-07-22 under the Creative Commons Attribution 4.0 license, which is not open source.