Cheapest priced copy (Strixhaven: School of Mages): $0.49 at Card Kingdom, near mint, their price list as of .
Codie, Vociferous Codex 
Legendary Artifact Creature — Book Construct · 1/4 · Rare · Strixhaven: School of Mages Promos · #253p
You can't cast permanent spells.
{4}, {T}: Add {W}{U}{B}{R}{G}. When you next cast a spell this turn, exile cards from the top of your library until you exile an instant or sorcery card with lesser mana value. Until end of turn, you may cast that card without paying its mana cost. Put each other card exiled this way on the bottom of your library in a random order.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
5 printings · $0.49 to $3.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Strixhaven: School of Mages Promos | 253p | Rare | $0.59 | $0.99 |
| Strixhaven: School of Mages Promos | 253s | Rare | — | $2.79 |
| Special Guests | 157 | Mythic | $0.99 | $0.99 |
| Strixhaven: School of Mages | 253 | Rare | $0.49 | $0.49 |
| Strixhaven: School of Mages | 357 | Rare | $1.79 | $3.99 |
11 rulings from Wizards of the Coast
- 16 April 2021If you cast a spell “without paying its mana cost,” you can’t choose to cast it for any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs, you must pay those to cast the spell.
- 16 April 2021While you control Codie (as much as anyone can really “control” Codie), you may cast any face of a modal double-faced card that’s an instant or sorcery face, even if the other face is a permanent face.
- 16 April 2021You exile the cards face up. All players will be able to see them.
- 16 April 2021If the card has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
- 16 April 2021A permanent spell is an artifact, creature, enchantment, or planeswalker spell. You may still play lands and cast instant and sorcery spells. Other effects can still put permanents onto the battlefield.
- 16 April 2021The types and mana value of a double-faced card in exile are determined by the characteristics of its front face. The mana value of a split card is the total mana value of both halves of the split card added together.
- 16 April 2021Codie’s activated ability is a mana ability. It can’t be countered or responded to, and you can activate it while casting a spell. If you do, that spell is “the next spell” you cast this turn.
- 16 April 2021The delayed triggered ability created by Codie’s second ability will resolve before the spell that caused it to trigger. That ability will resolve even if the spell is countered or otherwise doesn’t resolve.
- 16 April 2021If you exile your entire library without exiling an instant or sorcery card with a lesser mana value, you will randomize the exiled cards and they again become your library, ending the effect. You will not continue to exile and shuffle your library forever.
- 16 April 2021The mana value of the spell that caused the ability to trigger is determined only by its mana cost, no matter what the total cost to cast the spell was.
- 16 April 2021The last card exiled is not cast immediately. You may cast it until the end of the current turn. If you do not cast it, that card will remain in exile.