Muscle Sliver

Horned Sliver

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Birds of Paradise

Sliver Overlord

{3}: Search your library for a Sliver card, reveal that card, put it into your hand, then shuffle.
{3}: Gain control of target Sliver. (This effect lasts indefinitely.)

Door of Destinies

As Door of Destinies enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Talon Sliver

Mana Confluence

{T}, Pay 1 life: Add one mana of any color.

Heart Sliver

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Winged Sliver

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.