Cheapest priced copy (Time Spiral): $0.35 at Card Kingdom, near mint, their price list as of .
Screeching Sliver 
Creature — Sliver · 1/1 · Common · Time Spiral · #75
All Slivers have "{T}: Target player mills a card."
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
2 printings · $0.35 to $3.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Secret Lair Drop | 622 | Rare | — | $2.29 |
| Time Spiral | 75 | Common | $0.35 | $3.49 |
2 rulings from Wizards of the Coast
- 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.