Blur Sliver

(01/07/2013)
Abilities 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.

(01/07/2013)
If 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.

(01/07/2013)
If Blur Sliver leaves the battlefield during combat, any attacking Sliver creatures that came under your control this turn will continue to attack, even though they will no longer have haste.