Stormwing Entity

• WOTC Official Reminder Textofficial rules
  Scry — Look at the top N cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.
• WOTC Official Reminder Textofficial rules
  Prowess — Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.

• WWizards of the Coast2020-06-23
  Official Ruling
  Stormwing Entity's cost reduction applies just once, no matter how many instant and sorcery spells you've cast this turn.
• WWizards of the Coast2020-06-23
  Official Ruling
  Stormwing Entity's cost reduction applies even if the instant or sorcery spell you cast was countered or didn't resolve.
• WWizards of the Coast2020-06-23
  Official Ruling
  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 Stormwing Entity). The mana value of the spell remains unchanged, no matter what the total cost to cast it was.

Rulings via Scryfall