Cheapest priced copy (Dark Ascension): $0.35 at Card Kingdom, near mint, their price list as of .
Break of Day 
Instant · Common · Dark Ascension · #3
Creatures you control get +1/+1 until end of turn.
Fateful hour — If you have 5 or less life, those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Dark Ascension | 3 | Common | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 1 July 2013Because Break of Day affects only creatures you control when it resolves. It won’t affect creatures that come under your control later in the turn.
- 1 July 2013Break of Day checks your life total only at the time it resolves. Any creatures that gain indestructible will continue to be indestructible that turn even if you gain life.