I have been recently reading Alan Moore's run on The Saga of the Swamp Thing, and marveling at his writing. Moore has always been an impressive writer, but there are times when he constructs a phrase that stops you cold, and you have to read it again.
For example in this run Moore describes the Flash like this, "a man who moves so fast that his life is an endless gallery of statues." One sentence and Moore has cut to the heart of the character.
The Swamp Thing is another tragic character who is at first searching for his humanity, but later learns to accept what he has become, an earth elemental tasked with protecting the Parliament of Trees. (The group consciousness of all plants on Earth.)
Moore's writing is great and i found myself wanting to read just one more page before putting it down. Moore will also make you think, as this series is a long discussion about what makes a person human, and what makes a person a hero.