Cheapest priced copy (Ravnica: Clue Edition): $0.35 at Card Kingdom, near mint, their price list as of .
Leapfrog 
Creature — Frog · 3/1 · Common · Guilds of Ravnica · #42
This creature has flying as long as you've cast an instant or sorcery spell this turn.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
4 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Ravnica: Clue Edition | 89 | Common | $0.35 | — |
| Guilds of Ravnica | 42 | Common | $0.35 | $0.49 |
| The List | GRN-42 | Common | $0.35 | — |
| Ravnica Remastered | 49 | Common | $0.35 | $0.49 |