Rexby was a troll and fanboy that arrived in December 2012. He was at first perceived to be nothing more than a fanboy, but he flamed Topix Dinosaur Forum throughout early 2013. He mostly posted off-topic comments and spammed threads. He also claimed to have advanced hacking skills, which he didn't actually seem to have in possesion. Many users began feeding him, so he increased his rate of off-topic posts.

As he spammed further, he clashed with Pinky And Ze Brain, a troll who had just become a contributor. PAZB's experience in trolling helped him stop Rexby from doing too much damage to the forum, while Coprolite1, who initially believed Rexby would be a contributor and kept PAZB at bay, stopped protecting Rexby and also began flaming him.

In April 2013, Oasegenggam arrived at TDF and flamed Rexby, who was already war-weary after his constant battles with contributors, such as Paleoworld-101, and other trolls, such as Coprolite1. In February 2014, however, he returned, and began blasting insults at contributors. Most users tended to ignore him during his second coming, although others fed and fueled him through responses. Rexby continued to make off-topic posts until May 2014, when he was again scared away by Coprolite.