Mother Rat Matriarch

When Mother Rat Matriarch enters the battlefield,
you may search your library, graveyard, and exile
for any number of cards named Baby Rat Scout
and put them onto the battlefield. If you search
your library this way, shuffle it.
Other Rats you control get +1/+1.
"Her call echoes through the darkest tunnels,
summoning her children from every corner."