Quick answer: Unreal Niagara wind data interface reading zero in cooked builds? WindSource actors don't replicate to cooked clients - mark them as Always Relevant or use a baked wind texture.

Foliage sway looks great in editor PIE. Standalone cooked build: trees stand perfectly still.

Set Always Relevant

On the WindSource actor, Replicates = true, Always Relevant = true. Cooked clients need the actor in their world to query the data interface.

Or bake a wind texture

For static wind patterns, pre-bake a texture. Sample in shader; no actor required. Loses dynamic gusts; gains determinism.

Audit cooked content

UnrealEditor's Audit -> Cooked Content view shows which actors made it to the cooked package. Missing WindSource? Network relevance is the culprit.

“Replication relevance applies even in single-player cooked builds.”

For environmental effects that the player doesn't see directly, bake when possible. The fewer replicated actors, the fewer cooked-build surprises.