Cheapest priced copy (Double Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Fortify 
Instant · Common · Time Spiral Remastered · #18
Choose one —
• Creatures you control get +2/+0 until end of turn.
• Creatures you control get +0/+2 until end of turn.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
7 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Double Masters | 17 | Common | $0.35 | $0.49 |
| Jumpstart | 105 | Common | $0.35 | — |
| Magic 2014 | 19 | Common | $0.35 | $0.49 |
| Modern Masters 2015 | 17 | Common | $0.35 | $0.49 |
| The List | MM2-17 | Common | $0.35 | — |
| Time Spiral | 19 | Common | $0.35 | $0.49 |
| Time Spiral Remastered | 18 | Common | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 1 July 2013Creatures that come under your control after Fortify resolves won't get the chosen bonus.
- 1 July 2013You choose the mode as you cast Fortify, not as it resolves.