Cheapest priced copy (Classic Sixth Edition): $0.59 at Card Kingdom, near mint, their price list as of .
Tariff 
Sorcery · Rare · Weatherlight · #28
Each player sacrifices the creature they control with the greatest mana value unless they pay that creature's mana cost. If two or more creatures a player controls are tied for greatest, that player chooses one.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $0.59 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Classic Sixth Edition | 47 | Rare | $0.59 | — |
| Weatherlight | 28 | Rare | $0.59 | — |
5 rulings from Wizards of the Coast
- 4 October 2004The choice of creatures is made on resolution and not on announcement.
- 4 October 2004You can use mana abilities during the resolution of this spell if the player decides to pay the mana cost.
- 4 October 2004You choose whether to pay or not on resolution. If not, then you sacrifice the creature. You can choose to not pay if you control no creatures on resolution.
- 1 April 2008First the active player identifies the creature they control with the highest mana cost (and chooses one if there's a tie) and chooses whether to sacrifice it or pay mana. Then each other player in turn order does the same. All creatures sacrificed this way are sacrificed at the same time.
- 1 April 2008Although Tariff checks the mana value of the creatures on the battlefield, you need to pay the creature's actual mana cost (including color) to keep it on the battlefield.