Black Flash

Within DC Comics continuity the Black Flash is presented as an aspect of the Speed Force — specifically its dark or corrective side that returns speed-connected individuals to their source. Different storylines depict multiple incarnations or hosts linked to it (notably Wally West encounters, Bart Allen encounters, and narrative accounts tying Barry Allen and Eobard Thawne to versions of the Black Flash), and major Speed Force events (such as the Force Barrier's destruction and later Speed Force healing) influence its activity and containment.

Sources provide only limited, narrative-based description: the Black Flash is depicted as a visible, pursuit-capable, deathlike figure associated with speedsters. Specific scenes show it pursuing or taking speed-connected persons, freezing others in time during an encounter, and dissipating under certain narrative conditions; no consistent, detailed anatomical or costume description is supplied in the cited material.

The Black Flash functions as the Speed Force's reclaiming or 'death' agent for those connected to that power: it comes for speedsters who lose their connection or when the Speed Force seeks reclamation (examples include attempts on Wally West, taking Linda Park in one depiction, appearing when Bart Allen lost his powers, and hunting after the Force Barrier's destruction). In cited incidents it has frozen others in time except those connected to the Speed Force (Wally West encounter), hunted multiple targets during large Speed Force events, and been neutralized or trapped through extraordinary speedster actions (Wally racing it to the end of time causing it to dissipate; Zoom sacrificing himself to heal the Speed Force and thereby trapping the Black Flash). Some storylines also present persons associated with or transformed into incarnations of the Black Flash (Barry Allen and Eobard Thawne in cited summaries).