The Many Deaths of the Reverse Flash

[Dred]

Wally has a couple of villains that he killed who did not come back. The Suit, Cobalt Blue and Replicant. Savitar almost makes that list but he showed up for like a page and a half to die to Barry, then hasn't reappeared since.

Obviously none of them are hallmark villains but they were all involved in great stories. Though in Cobalt Blue's case that was in spite of the villain.