Eventide: Umbra Stalker

I've found this from this post at Mtgsalvation.com. The card is in Spanish and the translated text reads:

Umbra Stalker 4BBB
Creature - Elemental
Rare
Chrome - Umbra Stalker's power and toughness are each equal to the number of black mana symbols in mana costs on cards in your graveyard.
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A new mechanic, Chrome, is introduced. Here is the original card image: