It is a morph that only shows up under the correct level of Sub-D or higher. With 3Delight the morph shows up because 3Delight always automatically determines the correct level of SubD based on various factors. In other render engines (Iray, Lux, Octane, Firefly, etc.) you have to dial the correct level of SubD to see the difference. (Note that in Iray it is Render time SubD level all others it is Viewport subD level.)