Sloppity Bilepiper

Cascade has always lived on the spell that carries it, hardwired into a card's own text and paid for by mana value: cast the spell, and its triggered ability resolves first, digging through your library until it finds a cheaper nonland card to cast for free. This Demon breaks that assumption by conferring cascade rather than owning it, handing the keyword to the next creature you cast this turn instead of printing it on a body. The price is stiff. You feed it a creature and spend both mana and the tap, so the sacrifice and the once-per-turn window are the cost of the trigger. Cascade's own clause does the rest of the balancing: because it exiles until it hits a nonland card costing less, the payoff scales inversely with how cheap the creature you point it at is, largest when you aim it at your most expensive threats and thinnest when you fire it on a one-drop. Structurally it turns a sacrifice outlet into a free-cast enabler, converting stalled board presence into value the way an aristocrats deck already wants to, but pointing the return at your library's depths rather than at drain triggers. It lets you build cascade around a whole creature deck instead of around a single overcosted spell, and needing a body to sacrifice before you can fire means the engine always demands an input it cannot generate on its own.