Before the official spoilers for any upcoming Magic set start, the rumor community must rely on the good graces of anonymous privileged sources to drop hints, particularly on the MTGSalvation.com Rumor Mill forum. Today, a Little Birdie (yes, that's the source's username) posted for the first time on that board to allude to one of the strongest cards in Magic history as the inspiration for a card in Born of the Gods:
The seer looked confidant (sic) with his dark inspiration. After all, no pain no gain.
This is, of course, a reference to Dark Confidant, Bob Maher's Invitational-win design that infamously became regarded as the first member of the purported mega-cycle of "broken creatures that cost 1C." Bob himself is way too powerful to actually reprint in a real expansion - he'd break Standard wide open - but black effects that relate to paying life to draw cards are still very much fair game. Theros, as the Greek mythology-themed block, has scry as a returning mechanic, and we have yet to see a flavorful representation of haruspicy, or examining the entrails of victims. Viscera Seer exists, yes, but there are more places that flavor could go - such as a cantripping sorcery that involves paying X life to scry X. One thing's for certain - if the reference to Dark Confidant is considered to be apropos, then whatever the card turns out to be will definitely be in a lot of competitive decklists.