When using LoadSceneAsync, what feature allows for a seamless transition between scenes?

Using LoadSceneAsync with additive loading mode is the optimal approach for achieving seamless transitions between scenes in Unity. This feature allows you to load multiple scenes at once without unloading the currently active scene, enabling a smooth blend between the two environments. As one scene loads in the background, the player remains in the existing scene, which enhances the overall gaming experience by minimizing waiting times and interruptions.

Additive loading allows for the creation of larger, more complex game worlds composed of multiple segments that can be loaded and unloaded as needed. For instance, as a player transitions from one area of the game to another, you can seamlessly load the new area while still having the previous one active, providing a fluid gameplay experience.

This approach contrasts with immediate loading, which halts game progression until the new scene is entirely loaded, and single load mode, which would not allow for multiple scenes to be loaded simultaneously. Deferred loading refers to postponing the load, but it doesn't inherently support seamless scene transitions as effectively as additive loading does. Therefore, additive loading mode is the feature that best facilitates smooth scene transitions with LoadSceneAsync in Unity.