Gathering The Bijuu

This spell costs {1} less to cast for every beast
creature card on the battlefield under your control
or in your graveyard.
{3}{t}: Search your library for a beast creature card,
reveal it, and put it into your hand. Shuffle your
library afterwards. Put a counter on this card after
each use. Discard this card after 9 counters.
"Time to put a collar on all of you.... filthy beasts."