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.)
"Is that your coat of arms? Looks more like a shawl of branches to me!"
—Andreas the Imprudent, last words
Near Mint - $25.70
Lightly Played - $23.20
Played - $18.00
Heavily Played - $15.50
Damaged - $12.90
Near Mint Non-English - $25.70
Lightly Played Non-English - $23.20
Played Non-English - $18.00
Heavily Played Non-English - $15.50
Damaged Non-English - $12.90