Cheapest priced copy (Shadows over Innistrad): $0.99 at Card Kingdom, near mint, their price list as of .
Seasons Past 
Sorcery · Mythic · Shadows over Innistrad · #226
Return any number of cards with different mana values from your graveyard to your hand. Put Seasons Past on the bottom of its owner's library.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
3 printings · $0.99 to $14.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Tales of Middle-earth Commander | 529 | Rare | $14.99 | $14.99 |
| Shadows over Innistrad Promos | 226s | Mythic | — | $8.49 |
| Shadows over Innistrad | 226 | Mythic | $0.99 | $4.99 |
4 rulings from Wizards of the Coast
- 8 April 2016If a card in your graveyard has {X} in its mana cost, X is considered to be 0.
- 8 April 2016You choose which cards to return as Seasons Past resolves, not as you cast it.
- 8 April 2016The phrase "different mana values" compares the mana costs of cards in your graveyard to one another, not to Seasons Past. You may return a card with a mana value of 6.
- 8 April 2016A card with no mana cost, such as a land, has a mana value of 0.