The bitter feud between the Allen family and the Thawne family would span generations. Even in the 30th Century, President Thawne sought to recruit Bart Allen in his revenge campaign against the Allens, since Bart was half-Thawne himself. When that failed, Thawne mixed Bart's DNA with Thawne genetic material to create a speedster clone whom he named Thaddeus Thawne. Wheras Bart grew in a hyper-accelerated world, Thaddeus' childhood was the exact opposite; His development was super-slow, which led the young speedster to become more calculating and methodical. Thaddeus was also taught to hate the Allen family, and Impulse in particular. In addition to this modification, Thaddeus' growth and development was slowed. This is in contrast to Bart's accelerated development. This was done to give T