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 Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)
"Hup, two, three, four,
Dunno how to count no more."
—Mogg march
NM-Mint Foil - $19.10
Lightly Played Foil - $17.20
Moderately Played Foil - $15.30
Heavily Played Foil - $13.40
Damaged Foil - $9.60
NM-Mint Foil Non English - $19.10
Lightly Played Foil Non English - $17.20
Moderately Played Foil Non English - $15.30
Heavily Played Foil Non English - $13.40
Damaged Foil Non English - $9.60