Quandrix, the Proof (SOS 218)

Legendary Creature — Elder Dragon • Mana cost: {4}{G}{U} • Secrets of Strixhaven • Mythic

Flying, trample
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Instant and sorcery spells you cast from your hand have cascade.

Illustrated by Lucas Graciano.