An igniter includes a central electrode terminating in a firing portion including a plurality of prong tiers distributed axially on the firing portion. Each prong tier including at least one firing prong extending radially outward from the firing portion. The igniter body includes a port end to be received into an engine igniter port, and a shank. The firing portion of the central electrode extends from the shank opposing the port end. A dielectric casing can fully encapsulate the firing portion of the central electrode to define a dielectric barrier adjacent the firing prong. The igniter may include a generally cylindrical ground electrode defining a discharge cavity surrounding the central electrode. The ground electrode includes a plurality of ground prongs defined by the ground electrode and extending radially toward the firing portion. A plurality of apertures defined by the ground electrode are in fluid communication with the discharge cavity.