Magistrate's Scepter

The math here is brutal in the way only old artifacts are: dropping the Scepter costs three mana, then you spend four-and-a-tap three separate times to load it, then a fourth tap to cash three counters in for an extra turn. That is fifteen mana and four turns of doing nothing else just to buy a single additional turn, and the artifact taps for both halves so it cannot charge and fire in the same window. It belongs to the era when "take an extra turn" was treated as the most dangerous phrase in the game and priced like a long-term mortgage rather than a combo piece. Compared to a one-shot ritual of a time-walk, the Scepter is a counter-accumulator: it asks you to survive long enough to amortize the investment, and rewards untap effects, cost reduction, or proliferate that shortcut the loading phase. The design is honest about what it fears, which is repetition. Once the engine is online and the upkeep cost is mitigated, the extra turns chain, which is exactly why every modern extra-turn card carries an exile clause or a hard cap instead of a slow-charging battery. The Scepter is what taking-an-extra-turn looked like before designers learned to fear the loop: a machine you have to build piece by piece, on a clock, in public.