Cool Sliver 2

Emincence — Whenever another nontoken Sliver enters the battlefield under your control, if
Cool Sliver is in the command zone or on the battlefield, you may pay 1. If you do, create a 1/1 Sliver creature token that's all colors.
Sacrifice any number of Silvers: Put target Sliver card with converted mana cost equal to the
number of Slivers sacrificed this way -1 from a graveyard into the battlefield under your control.