Out Of Bounds [DIRECT]

: Set up "Overlap Events" so that entering a specific boundary box triggers a UI widget (like a warning) and starts the countdown logic. The Sporting Standard

In physical sports, out of bounds is a strict binary defined by the field's geometry.

: Instead of an invisible wall, many developers use a "Return to Play Area" message with a timer. If the player doesn't return, the system triggers a respawn.

: "Putting together" a recovery shot from out of bounds isn't allowed; the ball is dead, and you must play a new ball from the original spot with a penalty stroke. Methods on making "out of bounds" areas? - Unity Engine

: Create "kill volumes" or "trigger boxes" that detect when a player's character model leaves the playable area.