Welcome to the online game Stack. This is a online unblocked Puzzle Game. Stack is a new mobile game that requires skill, concentration, and precision. The object of the game is to stack as many blocks as possible, but it is important to be careful to avoid making mistakes. Incorrect placement can lead to blocks becoming smaller, which can hinder your ability to score high. Fortunately, there are some basic tips that can help you succeed in the game. Yup7 Games wishes you have fun playing Stack Unblocked Free Game!