Tezzeret the Schemer

The Tezzeret incarnation built for artifact-grindy midrange, where the +1 does double duty that most planeswalker plus abilities never attempt: it grows your artifact count toward the minus ability while also banking ramp and fixing. The Etherium Cell is the clever piece. Each token sits on the board as another artifact (feeding the X on the -2) until you cash it for mana of any color, so the card never forces you to choose between defending loyalty and assembling a kill. The -2 scales without a fixed ceiling: +X/-X means it can shrink a threat into the graveyard outright or, pointed at your own attacker, swing a race by adding power to an unblocked creature. Either way the artifacts that powered it stay around the following turn. What makes the design cohere is that every mode points back at the same resource. Most planeswalkers spread their loyalty across unrelated axes; this one wants exactly one thing on the battlefield, and all three abilities either make that thing or convert it. The ultimate stays inside that logic rather than breaking from it: the emblem reaches for an artifact you control and turns it into a recurring 5/5 each combat, so the more artifacts you have stocked, the more reliably you have a target waiting. The result reads as a value engine but plays as a removal-and-pressure package the moment your artifact count climbs, which is why it has never asked to be a generic four-mana inclusion so much as the payoff a whole shell is assembled around.