Flash & Green Lantern's Ultimate Power Combo Is a Planet-Killer

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DC Comics in the Sixties and Seventies was a wacky place, especially for Flash and theGreen Lantern. This was an era where Batman might order the Teen Titans to be steamrolled or where Lex Luthor's big plan could be to turn superheroes into children so they'd be easier to murder. Heroes were constantly finding new uses for their powers, some of which would go on to become staples of the character, and some of which would never appear again. A perfect example of the latter is the reveal that Flash and Green Lantern can effectively destroy a planet whenever they feel like it.

This was revealed in The Flash #222's «The Heart That Attacked The World!» In this story, Sinestro manages to team with the Weather Wizard in a plot seemingly aimed at the Scarlet Speedster. If the Weather Wizard will cover Earth's atmosphere in a global cloud to obstruct the Guardians' monitoring of Sinestro, the Yellow Lantern will give the Weather Wizard an advantage in his fight against Flash. This advantage turns out to be that whenever Flash uses his powers, random catastrophes will occur around him.

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Sure enough, when Weather Wizard and Flash clash again, bizarre consequences like flying trees and spontaneously collapsing mountains arise. Flash uses the opportunity of one such moment to snatch his shell-shocked foe before Green Lantern appears and apprehends Sinestro. Green Lantern discovers that Sinestro synchronized Flash's heart to Earth's core. Whenever his heartbeat changes pace — whether rising from power use or momentarily skipping a beat from a lightning bolt — the Earth will violently react. In fact, had Flash's heart stopped for longer, Earth would have been