Cheapest priced copy (Time Spiral Remastered): $0.49 at Card Kingdom, near mint, their price list as of .
Darkheart Sliver 
Creature — Sliver · 2/2 · Uncommon · Planar Chaos · #155
All Slivers have "Sacrifice this permanent: You gain 3 life."
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $0.49 to $15.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Planar Chaos | 155 | Uncommon | $0.69 | $15.99 |
| Time Spiral Remastered | 249 | Uncommon | $0.49 | $4.49 |
3 rulings from Wizards of the Coast
- 1 February 2007The player who controlled the Sliver that's sacrificed gains the life, not the controller of Darkheart Sliver.
- 1 July 2013Abilities that Slivers grant, as well as power/toughness boosts, are cumulative. However, for some abilities, like flying, having more than one instance of the ability doesn't provide any additional benefit.
- 1 July 2013If the creature type of a Sliver changes so it's no longer a Sliver, it will no longer be affected by its own ability. Its ability will continue to affect other Sliver creatures.