Bedlam Reveler

• WOTC Official Reminder Textofficial rules
  Prowess — Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.

• WWizards of the Coast2025-01-24
  Official Ruling
  Bedlam Reveler’s first ability can’t reduce the in its cost.
• WWizards of the Coast2025-01-24
  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 Bedlam Reveler’s first ability). The mana value of the spell is determined by only its mana cost, no matter what the total cost to cast that spell was.
• WWizards of the Coast2025-01-24
  Official Ruling
  If you have no cards in hand when Bedlam Reveler’s enters ability resolves, you just draw three cards.
• WWizards of the Coast2025-01-24
  Official Ruling
  An ability that triggers when a player casts a spell resolves before the spell that caused it to trigger. It resolves even if that spell is countered or otherwise leaves the stack without resolving.

Rulings via Scryfall