Saheeli Rai
The minus-two is the whole reason this planeswalker exists, and it spent its first months looking for the right partner. Creating a hasty artifact copy of a creature or artifact you control, then exiling that token at the next end step, reads like a value smoother: clone a token for an enter-the-battlefield trigger, copy your best artifact for an attack, get a one-shot body that doesn't clutter the board. But the loyalty arithmetic is what turned it into a tournament problem. Felidar Guardian, when copied this way, blinks Saheeli Rai herself on arrival: the original walker flickers, returns at base loyalty three, and the new Saheeli can immediately minus-two again to make another Felidar Guardian, looping into an arbitrarily large army of hasty cats. The combo half was banned outright, the kind of two-card kill that punishes a fair-looking three-mana planeswalker for a single end-step clause.
Strip the loop away and what remains is a deliberately modest design. The plus-one chips each opponent for one and smooths the next draw rather than building toward an emblem, so loyalty climbs slowly; the ultimate (three different-named artifacts straight onto the battlefield) is a payoff almost no fair deck is built to reach. The tension lives in that minus-two: the same line of text wants to be a careful midrange value tool and a combo engine at once, and the card never fully decides which one it is for.
