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 - $17.20
Lightly Played - $15.50
Moderately Played - $13.80
Heavily Played - $12.10
Damaged - $8.60
NM-Mint Non English - $17.20
Lightly Played Non English - $15.50
Moderately Played Non English - $13.80
Heavily Played Non English - $12.10
Damaged Non English - $8.60
Foil Prices
NM-Mint Foil - $47.80
Lightly Played Foil - $43.00
Moderately Played Foil - $38.30
Heavily Played Foil - $33.50
Damaged Foil - $23.90
NM-Mint Foil Non English - $47.80
Lightly Played Foil Non English - $43.00
Moderately Played Foil Non English - $38.30
Heavily Played Foil Non English - $33.50
Damaged Foil Non English - $23.90