Manaweft Sliver

Sliver creatures you control have "{T}: Add one mana of any color."

Their pearlescent scales are highly sought after by those who lack the instincts for self-preservation.

Commander Masters

"I see in their interconnectedness a strange embodiment of the natural order."
—Dionus, elvish archdruid

Secret Lair Drop

Jumpstart: Historic Horizons

The List

Magic 2014

Sliver creatures you control have "{T}: Add one mana of any color to your mana pool."

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.

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.