8. Black Hand
Before Geoff Johns got hold of him, William Hand was a strictly B-list villain for Green Lantern. However, beginning with the "Secret Origin" arc, the William Hand we are re-introduced to is an all together different animal. The "ick factor" was brought to the fore as Black Hand slowly became a bigger foe and eventual catalyst for the "Blackest Night" story. His background dealt with a family owned mortuary and Hand's fascination with the dead (some very disturbing events are alluded to) and death itself are the things of classic horror. The graphic murder of his family and eventual suicide we became privy to heralded a very adult edge to the Green Lantern comics, one that remains to this day. The mark Black Hand has left (and continues to imprint) make him an essential character to Lantern lore.