Another O'Neil text, but one with a far more distinguishable colour-pallet to its name.
After his run on Batman, O'Neil and frequent collaborator Neal Adams jumped onto Green Lantern/Green Arrow. While that might seem like an odd pairing at first, what with the pair only having the green motif to share between them, O'Neil managed to pioneer one of the medium's most iconic relationships during this period.
Founded with the intent of exploring the Nixonian United States, the series saw Oliver Queen and Hal Jordan embark on a Fear and Loathing-style road trip across the country, with Queen taking the position of the left-wing social justice activist, and Jordan that of the conservative stalwart. The pair would spar verbally (and physically) throughout the series, with the book at times looking more like a social critique of seventies America more-so than a simple superhero comic.
It's undeniably brilliant though, and while an image of a drug-addled Speedy may dominate reflections of the book, there is so much more to it than that. Another intelligent work, from one intelligent writer.