Here is the updated code

uttt.py

@@ -0,0 +1,100 @@
+class Game(object):
+    """The Ultimate game class."""
+
+    def __init__(self):
+        self.p1 = Player('x')
+        self.p2 = Player('o')
+        self.current_player = None  # self.decide_order()
+        self.subboards = [Board() for _ in range(9)]
+        self.mainboard = Board()
+
+    def decide_order(self):
+        # TODO: Add random option
+        text = "Who would like to go first? (1 / 2): "
+        while True:
+            player = input(text)
+            if player == "1":
+                return self.p1
+            elif player == "2":
+                return self.p2
+            else:
+                print("Please select either 1 or 2")
+
+    def has_winner(self):
+        pass
+
+    def get_board(self):
+        pass
+
+    def next_move(self):
+        pass
+
+    def message(self, msg):
+        pass
+
+    def run(self):
+        self.current_player = self.decide_order()
+        # TODO: Implement the main game loop
+        while True:
+            print("Nyaa~")
+
+    def __repr__(self):
+        pass
+
+    def __str__(self):
+        return self.get_board()
+
+
+class Board(object):
+    """Represents a standard 3x3 tic-tac-toe board."""
+    def __init__(self):
+        self.spaces = [" " for i in range(9)]
+        self.avail = set(self.spaces)
+        self.won = False    # make property
+
+    def check_if_won(self):
+        win_conds = {self.spaces[0] == self.spaces[1] == self.spaces[2],
+                     self.spaces[3] == self.spaces[4] == self.spaces[5],
+                     self.spaces[6] == self.spaces[7] == self.spaces[8],
+                     self.spaces[0] == self.spaces[3] == self.spaces[6],
+                     self.spaces[1] == self.spaces[4] == self.spaces[7],
+                     self.spaces[2] == self.spaces[5] == self.spaces[8],
+                     self.spaces[0] == self.spaces[4] == self.spaces[8],
+                     self.spaces[2] == self.spaces[4] == self.spaces[6]}
+
+        self.won = True in win_conds
+
+    def make_move(self, index, player):
+        """Mark the space at the given index with the given player's symbol"""
+        if index in self.avail:
+            self.spaces[index] = player.symbol
+            self.avail.remove(index)
+            self.check_if_won(player)
+        else:
+            raise Exception("Invalid Move! >:(")
+
+    def __repr__(self):
+        return str(self.spaces)
+
+    def __str__(self):
+        # TODO: List comprehensions yo
+        divider = "-----"
+        row1 = "{}|{}|{}".format(*self.spaces[:3])
+        row2 = "{}|{}|{}".format(*self.spaces[3:6])
+        row3 = "{}|{}|{}".format(*self.spaces[6:])
+        return "\n".join([row1, divider, row2, divider, row3])
+
+
+# Is this class even necessary?
+# Probably not. It should be removed.
+class Player(object):
+    """The player object"""
+    def __init__(self, symbol):
+        self.symbol = symbol
+
+    def __repr__(self):
+        return self.symbol
+
+
+if __name__ == "__main__":
+    Game().run()