Infernal Idol

The mana rock that eats itself for cards is an old idea, and this is a compact take on it. The first mode is unremarkable: a colorless-cost artifact that taps for black, the kind of fixing that sits quietly in a mono-black or two-color manabase. The second mode carries the whole design. For plus the tap and the sacrifice, it converts itself into a two-card draw at the cost of two life, folding a Sign in Blood refill into the same object that was ramping you a turn or two earlier. The structure is deliberate: it front-loads value as an accelerant, then cashes itself in for cards once the acceleration has done its job and you would rather have gas. Because the draw mode taps the artifact before sacrificing it, you cannot ramp and refill in the same turn, which is the constraint that keeps a three-mana rock from also being an on-demand card-advantage engine. Black has paid for its card draw in life since the earliest sets, and the two-life clause here is that same tax scaled to a two-card haul. What distinguishes it from a plain draw spell is the optionality: it is a rock until the moment you decide it is a Divination, and the choice of when to flip that switch is the only real decision the card asks of you.