Raven is the best-written immortal in ANY series. He gives a good example on why undeath is bad.
Not only that, but:
-He actually USES the wisdom of his immortality to his advantage
-His story, told to us in Xrd After Story A, is a cautionary tale, and very realistic on how people might exploit such amazing powers
-He didn't gain it through some magic rock like Vandal Savage or The Immortal (Invincible), but through a weird, out-of-nowhere experience where he died and was resurrected.
-Was so tired of his powers that he tried to willingly take his own life on MULTIPLE occasions (which, realistically, someone without the ability to die would ALSO do).
-Literally the only thing he values is the only thing as immortal as him: pain.
In short, Raven is both a cautionary tale on how immortality is a bad thing and, as mentioned prior, a well-written character because of the tragedy that befalls him. And that makes him the BEST immortal in all of fiction, bar none.
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