Rowan, Scholar of Sparks
Legendary Planeswalker — Rowan
Instant and sorcery spells you cast cost 
less to cast.
+1
: Rowan deals 1 damage to each opponent. If you've drawn three or more cards this turn, she deals 3 damage to each opponent instead.
-4
: 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."
Will, Scholar of Frost
Legendary Planeswalker — Will
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.
-7 : Exile up to five target permanents. For each permanent exiled this way, its controller creates a 4/4 blue and red Elemental creature token.
Anna Steinbauer
Rulings
Neither face’s first ability can reduce colored mana requirements of spells you cast.
(wotc • 2021-04-16)
For Will’s first loyalty ability, any effects that modify a creature’s power and/or toughness without setting them to a specific value (i.e. ones that don’t affect base power and/or toughness) will apply after its base power and toughness are set, regardless of the order those effects were created. The same is true for counters that modify its power and toughness.
(wotc • 2021-04-16)
For Rowan’s emblem, you can pay {2} only once. You can’t pay more to copy the spell more than once.
(wotc • 2021-04-16)
To determine the total cost of a spell, start with the mana cost or alternative cost you’re paying, add any cost increases, then apply any cost reductions (such as that of Rowan or Will’s first ability). The mana value of the spell is determined only by its mana cost, no matter what the total cost to cast the spell was.
(wotc • 2021-04-16)
Related Cards
Printings
Rulings
Neither face’s first ability can reduce colored mana requirements of spells you cast.
(wotc • 2021-04-16)
For Will’s first loyalty ability, any effects that modify a creature’s power and/or toughness without setting them to a specific value (i.e. ones that don’t affect base power and/or toughness) will apply after its base power and toughness are set, regardless of the order those effects were created. The same is true for counters that modify its power and toughness.
(wotc • 2021-04-16)
For Rowan’s emblem, you can pay {2} only once. You can’t pay more to copy the spell more than once.
(wotc • 2021-04-16)
To determine the total cost of a spell, start with the mana cost or alternative cost you’re paying, add any cost increases, then apply any cost reductions (such as that of Rowan or Will’s first ability). The mana value of the spell is determined only by its mana cost, no matter what the total cost to cast the spell was.
(wotc • 2021-04-16)