Cheapest priced copy (Magic 2014): $0.99 at Card Kingdom, near mint, their price list as of .
Predatory Sliver 
Creature — Sliver · 1/1 · Common · Magic 2014 · #189
Sliver creatures you control get +1/+1.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
2 printings · $0.99 to $6.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Magic 2014 | 189 | Common | $0.99 | $4.49 |
| Secret Lair Drop | 654 | Rare | — | $6.49 |
2 rulings from Wizards of the Coast
- 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 you change the creature type of a Sliver you control 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 you control.