We present a new infinite class of gravitational observables in
asymptotically Anti-de Sitter space living on codimension-one slices of the
geometry, the most famous of which is the volume of the maximal slice. We show
that these observables display universal features for the thermofield-double
state: they grow linearly in time at late times and reproduce the switch-back
effect in shock wave geometries. We argue that any member of this class of
observables is an equally viable candidate as the extremal volume for a
gravitational dual of complexity.
