Hero card

Dive Down

Instant

SpellUsed once: what it does depends on when you cast it

Needs: Valiant

Gives: Spells

Not in winning lists yet: read from the card text and the graph

Build a deck with Dive Down as the hero

Makes it work

Emberheart Challenger · Veteran Guardmouse · Nettle Guard · Whiskerquill Scribe · Whiskervale Forerunner · Mouse Trapper · Seedglaive Mentor · Flowerfoot Swordmaster

Benefits from it

Elusive Otter · Drake Hatcher · Rediscover the Way · Elemental Mascot · Ojer Pakpatiq, Deepest Epoch

Use instead if you don't have it

Magic Damper · Shore Up · Octopus Form · Chase Inspiration · Fleeting Reflection · Blossoming Defense

Cards in the meta that answer it

Countersculpt (Azorius Control) · Inevitable Defeat (4-Color Control) · No More Lies (Azorius Control) · We Say Thee Nay! (Dimir Aggro)