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
Near Mint - $13.90
Lightly Played - $11.10
Moderately Played - $9.70
Heavily Played - $8.40
Damaged - $7.00
Near Mint Spanish - $13.90
Lightly Played Spanish - $11.10
Moderately Played Spanish - $9.70
Heavily Played Spanish - $8.40
Damaged Spanish - $7.00
Foil Prices
Near Mint Foil - $45.10
Lightly Played Foil - $36.10
Moderately Played Foil - $31.60
Heavily Played Foil - $27.10
Damaged Foil - $22.60
Near Mint Foil Spanish - $45.10
Lightly Played Foil Spanish - $36.10
Moderately Played Foil Spanish - $31.60
Heavily Played Foil Spanish - $27.10
Damaged Foil Spanish - $22.60