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 - $29.00
Near Mint Non-English - $29.00
Lightly Played - $26.10
Lightly Played Non-English - $26.10
Played - $20.30
Played Non-English - $20.30
Heavily Played - $17.40
Heavily Played Non-English - $17.40
Damaged - $14.50
Damaged Non-English - $14.50