Cheapest priced copy (Legions): $8.49 at Card Kingdom, near mint, their price list as of .
Essence Sliver 
Creature — Sliver · 3/3 · Special · Time Spiral Timeshifted · #8
Whenever a Sliver deals damage, its controller gains that much life.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
3 printings · $8.49 to $49.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Legions | 13 | Rare | $8.49 | $49.99 |
| Secret Lair Drop | 612 | Rare | — | $8.49 |
| Time Spiral Timeshifted | 8 | Special | $9.49 | $29.99 |
3 rulings from Wizards of the Coast
- 4 October 2004You only gain the life when the triggered ability resolves. If you are reduced to zero life before the ability resolves, you will lose before gaining the life.
- 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.
- 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.