The Green Lantern Corps are among the strongest forces in the DC Universe, but even they can fall prey to villains — and two of them can be defeated by the Joker from The Dark Knight. There are thousands of Green Lanterns spread out across the universe, each responsible for a sector of space and each armed with a Green Lantern Ring, powered by the user's willpower. Unfortunately, that willpower is not enough to save Hal Jordan and Alan Scott from the Clown Prince of Crime — and a common household object.
Green Lantern is one of the first successful legacy titles belonging to a group of heroes rather than a single individual. Alan Scott was introduced in 1941 during the Golden Age of Comics Book during World War II, and his ring functioned via magic. In 1959, Hal Jordan was used to revitalize the property and transformed the concept of Green Lantern intoa Green Lantern; there were many, all stylized as interstellar space police. Eventually Alan Scott would be retconned into the ranks of the Green Lantern proper...and unfortunately bring his weaknesses with him.
Related: Green Lantern Is Broken (But DC Refuses To Fix Him)
Alan Scott's Green Lantern ring had a crippling weakness: the ring's magic could not affect any object made out of wood. Considering that Scott was active in the 40s, a great many things were made out of wood at the time (and many still are), although he was able to get around this weakness quite easily. The same cannot be said for Hal Jordan; his ring had a different weakness and could not affect any object with the color yellow. This means both Alan Scott and Hal Jordan could be defeated with a no. 2 pencil...a writing implement the Joker memorably used to deadly effect in The Dark Knight.
Hal Jordan's
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