The most dangerous assassins have come back in Sift Heads World Act 4 unblocked game. They are beginning an extremely interesting adventure with new challenges. And you should give them a hand so that they can eliminate all of the enemies as well as earn a lot of money. In the world of Sift Heads World Act 4, you need to find the target and aim before you take down them. Don't forget to reload, unlock other better weapons and uncover every secret in the story! Good luck!