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.)
Near Mint - $23.60
Lightly Played - $18.90
Moderately Played - $16.50
Heavily Played - $14.20
Damaged - $11.80
Near Mint Spanish - $23.60
Lightly Played Spanish - $18.90
Moderately Played Spanish - $16.50
Heavily Played Spanish - $14.20
Damaged Spanish - $11.80