Rush of Knowledge
Most card-draw spells fix their yield: pay the cost, get a number. This one pegs its payoff to the most expensive thing you have already resolved, which means the spell is only as good as your board is bloated. That dependency is the design, not a flaw in it. It rewards decks built around a single fat permanent: a colossal creature, a high-cost artifact, a planeswalker whose mana value dwarfs everything else. Land in play with a nine-drop and this refills your hand for five mana in one shot; cast it with nothing but lands and dorks down and you have drawn a card or two for a bad rate. The card asks you to invest first and reap second, sequencing the big threat before the refuel so the count climbs. It pairs cleanly with cheats: anything that puts an oversized permanent into play ahead of its cost turns this into a payoff for the same setup. The risk is structural. Whatever inflates your greatest mana value is also the most fragile thing on your board, so a removal spell aimed at your fatty does double duty, cutting both your wincon and your draw. The bigger the engine, the bigger the target: that tension is what separates this from a flat blue cantrip and forces you to build the deck around it rather than slot it in.
