User blog comment:Emptylord/Season 3 - PBE Patch Notes/@comment-4022742-20121112155322

"Dreadful Visage
 * UNIQUE PASSIVE: Your ability damage reduces your target's Magic Resist by 5 for 5 seconds (stacks up to 3 times).
 * +70 ability power,
 * +250 health
 * +20 magic penetration

This is an old rumour for a Season 3 item, but partially matches the new Black Cleaver. The passive may receive an update to match the Black Cleaver."

The only thing that bothers me about this is the inconsistency between the passives. With every item that decreased magic resist you had an armor reduction counter part: Although all the stats didn't really add up, you generally had one of each before they started messing with it... With the change to Black Cleaver decreasing Percentage damage, it would make more sense for Dreadful Visage to reduce in Percentage as well.
 * Void Staff & Last Whisper
 * Malady & Black Cleaver
 * Abyssal Scepter & Youmuu's Ghostblade
 * Haunting Guise & Stark's Fervor

Looking forward to the changes.