Thunder Dragon 2, released on October 1st, 1993, and later again in a revised version on November 9th, 1993, represents a sequel that likely builds upon the success of the first Thunder Dragon. It is assumed to be another vertical shooter continuing the saga, possibly with enhanced graphics, new enemies, and improved gameplay mechanics. The development team and publisher likely remain uncredited but it's a testament to the original's appeal that it warranted a sequel. 

Thunder Dragon 2 (1st Oct. 1993)

Thunder Dragon (4th Jun. 1991)