A-Rowan, Scholar of Sparks // A-Will, Scholar of Frost
Rowan and Will, the Eldraine twins, split across a modal double-faced card, and you commit to one of them at the moment you cast: there is no flip, no transform, no way to have both loyalty abilities on the board from a single card. That constraint is what makes the shared static so pointed. Whichever sibling you choose costs the same three mana and shaves a generic off your instants and sorceries, so the deck around them barely changes: you are choosing a plan, not a shell. Rowan is the aggressive line. Her plus deals 1 to each opponent, tripling to 3 once you have drawn three cards in a turn, so she turns a spellslinger's natural card flow into a clock; her ultimate hands you an emblem that, for two mana, copies each instant or sorcery you cast afterward (only those, not creatures or other permanents). Will is the defensive mirror. His plus shrinks a creature to base 0/2 until your next turn, a repeatable tempo brake rather than removal; his minus refills the hand; and his eight-loyalty exile clause is a board sweep with an invoice attached, clearing up to five permanents while handing each controller a 4/4 Elemental for every permanent it lost. The design trick is that draw-to-burn and draw-to-stabilize both want the same cheap noncreature spells, and the discount is the bridge that lets one pile of cards run either twin.
Rules text
less to cast.
+1: Rowan, Scholar of Sparks deals 1 damage to each opponent. If you've drawn three or more cards this turn, she deals 3 damage to each opponent instead.
−5: You get an emblem with "Whenever you cast an instant or sorcery spell, you may pay 
. If you do, copy that spell. You may choose new targets for the copy."
//
Instant and sorcery spells you cast cost less to cast.
+1: Up to one target creature has base power and toughness 0/2 until your next turn.
−3: Draw two cards.
−8: Exile up to five target permanents. For each permanent exiled this way, its controller creates a 4/4 blue and red Elemental creature token.