Keira and Liam, Shadow Couple

Lifelink, deathtouch
{b},{t},Pay 1 Life, discard a card, exile the top two cards of your library: Destroy target creature. That creatures owner exiles X cards from top of his or hers library and loses X life where X is the converted mana cost of the destroied creature.
They once were the parents of Renaras most skilled assassin.