Cheapest priced copy (Amonkhet): $0.35 at Card Kingdom, near mint, their price list as of .
Consuming Fervor 
Enchantment — Aura · Uncommon · Amonkhet · #126
Enchant creature
Enchanted creature gets +3/+3 and has "At the beginning of your upkeep, put a -1/-1 counter on this creature."
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Amonkhet | 126 | Uncommon | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 18 April 2017If Consuming Fervor is removed, the enchanted creature keeps the -1/-1 counters but loses the +3/+3 bonus.
- 18 April 2017If one creature is enchanted with two Consuming Fervors, it has the triggered ability twice and it gets two -1/-1 counters at the beginning of your upkeep.