Common:35
It does, however, have some fierce competition, Burgeoning, for instance, offers a similar strong land-playing ability that even beats Exploration in Commander
Plus, its easy for anyone to start investing since information about card values and rarity is so accessible
I think the only way that this sees play is if the -2 ability ends up being a lot better than it seems
Some games these are designed to fit include: Agricola, Alhambra, Battlecore, Blue Moon City, Castle Panic, Caverna, Cuba, Dice Town, Dominion, Islebound, Jambo, Kingdom Builder, Le Havre, Lord of the Rings, Machu Pichu, Memoir '44, Road Kill Rally, San Juan, Snowdonia, Stone Age, Summoner Wars, Thebes: The Tomb Raiders, Trailer Park Wars, Warhammer Quest and Witches Brew
So, they attack you with a 6/3 mouse that's punishing to kill, one that often has trample or double strike