Rock Hydra
Creature — Hydra{X}{R}{R}0/0
This creature enters with X +1/+1 counters on it. For each 1 damage that would be dealt to this creature, if it has a +1/+1 counter on it, remove a +1/+1 counter from it and prevent that 1 damage. {R}: Prevent the next 1 damage that would be dealt to this creature this turn. {R}{R}{R}: Put a +1/+1 counter on this creature. Activate only during your upkeep.
Colour identity Red
In short
Rock Hydra has 9 listed printings; the most valuable is the Retro Frame printing from 30A at US$76.99 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.
Every Rock Hydra printing
Retro Frame
Rock Hydra
30A · 464
TCGplayer market
US$76.99
Rock Hydra
2ED · 172
TCGplayer market
US$47.91
Rock Hydra
30A · 167
TCGplayer market
US$14.98
Collector's Edition
Rock Hydra
CED · 172
TCGplayer market
US$8.00
Rock Hydra
3ED · 173
TCGplayer market
US$3.89
Rock Hydra
LEA · 171
TCGplayer low only
US$800.00
Rock Hydra
LEB · 172
TCGplayer low only
US$154.99
International Edition
Rock Hydra
CEI · 172
TCGplayer low only
US$14.13
Rock Hydra
SUM · 173
Price not tracked