Blocks, regions, inventories, and spawned entities

Blocks and regions

Use Call Method with No Object for static plot/world operations. Set Block changes a position; Set Region changes a bounded area between corners; Clone Region uses source and destination anchors. Typed Item inputs represent the block material, while block data Strings configure supported state.

Keep all positions inside the play area and choose a small test region before applying a large edit. Loops/regions consume execution work; a large plot is not an unlimited edit budget.

Other world operations cover biome changes, growth, bone meal, random ticks, trees, signs, heads, brushable contents, and block-property reads. A block operation can require an appropriate block state: a sign-text operation needs a sign, and a container operation needs a container.

Containers and player inventories

Container actions address a Location and optional slot/content values. Player inventory actions need a Player receiver. These are different destinations. Check whether the operation edits one slot, replaces contents, adds items, removes matching items, or simply tests for room.

Inventory indices exposed by Craftly are 1-based where labelled. Player inventory slot mappings and container slot ranges differ; read the chosen argument label instead of assuming every slot has the same meaning.

Item frames

Place Item Frame uses the frame block Location, facing, and Glow flag. Get Item Frame at Location returns a typed target for later changes. Frames are preserved as decorations rather than following transient mob/display cleanup. Check attachment/location/facing before assuming a target exists.

Spawned entities

Spawn actions create mobs, items, experience orbs, displays, armor stands, interactions, TNT, falling blocks, crystals, vehicles, fangs, fireworks, Shulker bullets, Eyes of Ender, or potion clouds using their available typed inputs.

A spawn action does not automatically mean its entity becomes the next block’s selected receiver. Capture/retrieve a compatible target through the supported context/operations before calling target methods. New entities belong to the running plot and follow its limits and cleanup.

Persistent scenery versus runtime state

Use Build for permanent construction. Use runtime entities/world operations for game behavior that you deliberately initialize and clean up. Save Variables preserve supported data graphs, not arbitrary physical entities or a full automatic world rollback.

See native behavior and the individual operation entries for restrictions on explosive, private-presentation, spawning, and event actions.