Cheapest priced copy (Tenth Edition): $0.99 at Card Kingdom, near mint, their price list as of .
Rootwater Matriarch 
Creature — Merfolk · 2/3 · Rare · Tempest · #83
{T}: Gain control of target creature for as long as that creature is enchanted.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.99 to $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Tenth Edition | 103 | Rare | $0.99 | $1.99 |
| Tempest | 83 | Rare | $1.49 | — |
4 rulings from Wizards of the Coast
- 4 October 2004Can target an unenchanted creature but has no effect on that creature.
- 1 August 2005A creature is “enchanted” if it has any Auras attached to it.
- 15 July 2007Unlike many similar creatures, Rootwater Matriarch untaps as normal during your untap step. Whether it’s tapped or untapped has no bearing on the control-change effect.
- 1 February 2009The control effect applies so long as at least one Aura is attached to the creature, and will continue to apply even if Rootwater Matriarch has left the battlefield. The effect ends if at any time the creature has no Auras on it.