Twice-Told-Tales: Devious Duplicates Developed Deviously

Two of the most prolific adversaries that the Greatest Superheroes of parallel planets ever faced were Kanjar Ro and Vandal Savage. Although their counterparts on each other's world were different villains, during a series of  schemes these twin terror's actions mirrored one another, It began shortly after they were both defeated approximately the same time, at the hands of the Justice League and Society respectively.

Both malicious masterminds hatched plots whereby they utilized stolen super-science in their attempted conquests of their respective universes  while achieving vengeance versus their bitter foes. These pawns would be directed towards a quintet of both teams' members. While Kanjar Ro's sinister spawn replicated  the Leaguers... Vandal Savage's approach was to eliminate his foes in the Society once and for all.

Thinking these beings would lead the two teams into traps, the second half of their plans were hatched when Ro utilized his Energi-Rod to shift Earth-One from its orbit closer to where he was located while on the planet Rann; and when Savage utilized a mysterious wand exerting his influence over his adversaries (Vandal Savage's true counterpart was Kru-El the Kryptonian, who mostly resided in the Phantom Zone, although on one occasion battled the Justice League).

Kanjar Ro's true counterpart was the dictator known as Blakfu, king of the Mole Men*. Utilizing paralyzing electrical currents and other weaponry similar to his counterpart, Blakfu like Kanjar Ro made as a recurring the Wonder Woman of his Earth. Only instead of facing Wonder Woman’s allies in the Justice Society, he made enemies of the girls of Holliday College.

With such awesome power in the palms of their hands, and with their hated foes permanently out of the picture, they would've been successful in this regard. However, despite their incredible intellect and bountiful resources, it was the ego of these two villains that ultimately go the better of them at the end of the day. 

Kanjar Ro was outwitted by the superior strategies of his arch-enemy archaeologist Adam Strange, protector of Rann. This was the second of two tries at defeating Strange and the League early in their costumed careers.

Savage found his second solo foray versus the Society fail after the intervention of his first superhero foe, Green Lantern. This attempt took place shortly after Vandal had briefly captured and held that team comatose in his Mammoth Cave hideout. 

During these twice-told-tales, the villains of the piece found their failures mirrored in one another. The assembled Justice League quickly overpowering Kanjar Ro in his throne room, while Savage himself was surrounded and vanquished at an undisclosed location. In fact, this was first hinted at previously as being an untold tale. Both Kanjar-Ro and Vandal Savage years later would have two more consequences battles versus the League and Society, but those are tales left to be told for another day!

* Blakfu with his Mole Men appeared in Wonder Woman #s 4, 35, 47, and 57.  Kanjar Ro with his minions appeared in Justice League of America #3, 24, 120-121, 138-139. Three additional appearances of Kanjar Ro versus the Justice League mirrored Savage's three known battles with the Justice Society.