Cheapest priced copy (Urza's Legacy): $6.99 at Card Kingdom, near mint, their price list as of .
Second Chance 
Enchantment · Rare · Urza's Legacy · #41
At the beginning of your upkeep, if you have 5 or less life, sacrifice this enchantment and take an extra turn after this one.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
1 printing · $6.99 to $159.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Urza's Legacy | 41 | Rare | $6.99 | $159.99 |
4 rulings from Wizards of the Coast
- 4 October 2004It is not optional.
- 4 October 2004The ability will only trigger if you have 5 or less life at the beginning of upkeep. This is checked again at the start of resolution and nothing happens if you do not still have 5 or less life.
- 15 June 2010On resolution of the trigger you have to sacrifice this card if you have 5 life or less. If you can't (because it is not on the battlefield, for example), then you still take an extra turn after this one.
- 8 December 2022If multiple "extra turn" effects resolve in the same turn, take them in the reverse of the order that the effects resolved. In other words, the most recently created extra turn is taken first.