Block it

You may play this game with your friend face-to-face or with an AI.

The goal is to get to the other side of the grids. Player who reached any of the boxes there first wins. At your turn, you may choose to either move by one grid or to block your opponent's way. However, please note that the system will leave at least one way out for your opponent.
The best strategy to win is to lure your opponent into an area and then block all other exits except the entrance.