Like real-world Hula Hoop, the goal is to keep the hoops moving. If all hoops stop, you lose with score zero. Winning requires keeping the hoops moving through four levels, which are indicated by the hearts on the left of the screen: the more hearts the longest lived. The level advances when the current countdown reaches zero.
Each level ls increasingly difficult. With each new level, not only is the countdown time longer; but, each new hoop is launched at a slower velocity making it more likely to stop. Additionally, with each advancing level, when two hoops overlap one is more likely to follow the other, which also makes the hoops more likely to reach an equilibrium that stops all hoop movement.
The up button adds one hoop. When a hoop is added, the current countdown starts over. Hoops are launched at a random position with a random velocity. The down arrow removes the slowest hoop, for example, a hoop that has stopped moving altogether. The countdown does not restart.
More information at https://wecodemakecode.com/2019/12/02/using-hula-hoop-game-in-makecode-arcade/