Order of the Acorn

Each creature gets +1/+1 for each other
creature on the battlefield that shares at least
one creature type with it. (For example, if two Squirrel Warriors and a Squirrel Druid are on
the battlefield, each gets +2/+2.)

"The Order of the Acorn needs at least one more intrepid, furry hero to round out its collection of furry fighters."