Corrupted Conviction
Functionally, this is Village Rites with a different name: one mana, sacrifice a creature as an additional cost, draw two. The template goes back to Altar's Reap, and every version since has been priced on the same premise, that a creature already committed to dying is worth two cards on the way out. What makes the effect worth running is the additional-cost structure itself. Because the sacrifice is baked into casting rather than a repeatable outlet, you cannot fire it with an empty board or chain it into itself, but you also do not need to assemble a separate outlet to cash in a dying body: the spell is its own conversion. That is the entire pitch for a deck stocked with expendable attackers, tokens, or creatures carrying death triggers. The instant timing is where the card earns its keep. Sacrificing in response to targeted removal turns an opponent's answer into two cards, and it lets you feed a graveyard or fire an aristocrat payoff at the precise window you want it. The requirement is a creature you were content to lose, and in a board built to supply those, one mana for two cards at instant speed sits at the ceiling for this kind of draw.

