Cheapest priced copy (Revised Edition): $0.35 at Card Kingdom, near mint, their price list as of .
Reverse Polarity 
Instant · Common · Antiquities · #7
You gain X life, where X is twice the damage dealt to you so far this turn by artifacts.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
4 printings · $0.35 to $0.39 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Revised Edition | 36 | Uncommon | $0.35 | — |
| Antiquities | 7 | Common | $0.39 | — |
| Foreign Black Border | 36 | Uncommon | — | — |
| Summer Magic / Edgar | 36 | Uncommon | — | — |