Wrath of Corax was given to Ghosts of Retribution in 307.M41 as a gift to celebrate their Founding. As strange is it might be, no other Raven Guard successors participated and the sword was given by a representative from the High Lords of Terra.
However sword served for the Chapter just a little more than a decade, in 317 it was lost on Hades, where Chapter Master was released from captivity by the Eldar. While trying to reestablish contact with his brothers, Chapter Master ventured to an ancient abandoned shipwreck and by accident overloaded nuclear energy reactors, resulting in an explosion of apocalyptic proportions. Chapter Master was ripped out of this reality and stood on the Gates of Limbo. This was the last "place" where Wrath of Corax was seen before Chapter Master struck a deal with Laughing God.
Wielder of Wrath of Corax gets (+20) bonus to any Charisma or Willpower tests that are used against Raven Guard or their successors because of the respect they have for this ancient relic.
Dark Steel is a psycho-active material, wielder can cast psychic powers on Wrath of Corax, use it to deflect enemy psychic powers and it increases wielder's Psychic Rating by 1.
Legend says, that Corax often polished this sword before the battle, looking at how black the blade was. It is believed, that with a skill it is possible to tell how dark is the future that awaits you.