A construction toy with a power module is disclosed. The construction toy has one power module and one or more slave members linked together to form a loop. The power module has a core assembly with a flexible rod which can be twisted to store potential energy from the kinetic energy when the rod is twisted. Upon releasing, the twisted rod in the core assembly unwinds itself to release the stored potential energy and causes the entire construction toy in motion. An anti-snap mechanism is incorporated to ensure the flexible rod does not snap in the event of over winding.