Cheapest priced copy (Strixhaven: School of Mages Promos): $0.49 at Card Kingdom, near mint, their price list as of .
Sparring Regimen 
Enchantment · Rare · Strixhaven: School of Mages · #293
When this enchantment enters, learn. (You may reveal a Lesson card you own from outside the game and put it into your hand, or discard a card to draw a card.)
Whenever you attack, put a +1/+1 counter on target attacking creature and untap it.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $0.49 to $3.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Strixhaven: School of Mages Promos | 29p | Rare | $0.49 | $3.49 |
| Strixhaven: School of Mages Promos | 29s | Rare | — | $1.29 |
| Strixhaven: School of Mages | 29 | Rare | $0.49 | $0.49 |
| Strixhaven: School of Mages | 293 | Rare | $0.49 | $0.49 |
4 rulings from Wizards of the Coast
- 16 April 2021If instructed to learn, you may do nothing. Discarding a card and putting a Lesson card into your hand are both optional.
- 16 April 2021If you bring a card into the game from outside the game in a Sealed Deck or Booster Draft event, you may select only a card that is in the card pool that you built your deck from.
- 16 April 2021If you bring a card into the game from outside the game in a Constructed tournament (or a Constructed game played under tournament conditions), you may select only a card from your sideboard. In casual Constructed games, the card comes from your collection.
- 16 April 2021If a card is brought into the game from outside the game, it will stay in the game until it ends or until its owner leaves the game, whichever comes first.