  Active tuning of the scattering of particles and metasurfaces is a highly
sought-after property for a host of electromagnetic and photonic applications,
but it normally requires challenging-to-control tunable (reconfigurable) or
active (gain) media. Here, we introduce the concepts of anisotropic virtual
gain and oblique Kerker effect, where a completely lossy anisotropic medium
behaves exactly as its anisotropic gain counterpart upon excitation by a
synthetic complex-frequency wave. The strategy allows one to largely tune the
magnitude and angle of a particle's scattering simply by changing the shape
(envelope) of the incoming radiation, rather than by an involved medium-tuning
mechanism. The so-attained anisotropic virtual gain enables directional
super-scattering at an oblique direction with fine-management of the scattering
angle. Our study, opening a unique light-management method, is based on
analytical techniques that allow multipolar decomposition of the scattered
field, and is found, throughout, to be in excellent agreement with full-wave
simulations.
