setsimulationradius

Sets the client’s physics simulation radiusSimulation radiusThe spherical region (in studs) around a player where the client has physics authority. Parts inside are simulated locally; parts outside are server-authoritative. Default: ~1000 studs. — the distance from the player’s character within which the client has authority over physics simulation. Parts outside this radius are simulated by the server. Setting a large value (e.g., math.huge) gives the client physics authority over everything in the workspace.

The client sends the requested radius to the server via internal replication. Some servers cap or validate the radius. Combined with getsimulationradius() to check the current effective radius.