Level: 36

Type: boar

Potion: major mammalogy

Alb Frontier

Snowdonia: 26k, 57k

Grunge turns into a very big trophy. He's found at 26, 57 in Snowdonia. No other mobs spawn near him. Directions: From Castle Snowdonia, walk west. Just before you reach Castle Myrddin, you'll pass a small grove of trees. Look there for Grunge. (Prior to version 1.70, Grunge was found at 20, 41 in Snowdonia.)