Sliver Plaguelord

When Sliver Plaguelord enters the battlefield, sacrifice any number of Slivers. For each sliver sacrificed this way, each player gets a poison counter.
Slivers have infect.
{p/b}{p/g}{p/r}{p/u}{p/w}: Search your deck for a Sliver and put it onto the battlefield under your control, you get a poison counter.
"The end of mortality."