The Flash - Season 9 File

Eddie summoned Barry’s greatest past rivals—Reverse-Flash, Zoom, Savitar, and Godspeed—for one final assault.

Both returned to assist in pivotal moments, reinforcing the theme of legacy. The Flash - Season 9

Barry chose empathy over violence, convincing Eddie to coexist in balance rather than destruction. Memorable Returns and Milestones resurrected by the Negative Speed Force

Eddie Thawne , resurrected by the Negative Speed Force, became the avatar Cobalt Blue . The Flash - Season 9

Barry recruited a "Rogues Squad" of former enemies, including Hartley Rathaway (Pied Piper) and Mark Blaine (Chillblaine), to counter the threat.

As a farewell to the Arrowverse , the season featured several high-profile cameos:

Returned in Episode 9 as The Spectre to help Barry save the newly reborn Multiverse.