Rukarumel, Biologist

As Rukarumel, Biologist enters, choose a creature type.
Slivers you control and nontoken creatures you control are the chosen type in addition to their other creature types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 1/1 colorless Sliver creature token.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Gemhide Sliver

All Slivers have "{T}: Add one mana of any color."