In early 1094, Tatikios was placed in charge of guarding Alexius' tent at Pentegostis. Here he discovered the plot of Nikephoros Diogenes, son of the former emperor Romanus IV Diogenes, to kill the emperor. Nicephorus was an old friend of Alexius and Tatikios and Alexius was reluctant to punish him, but it was clear that Nicephorus was ambitious for the throne. Nicephorus was exiled and was eventually blinded. Later in 1094, Tatikios attended the synod of Blachernae which condemned Bishop Leo of Chalcedon, presumably performing some function of security. In the records of this synod Tatikios is given the court title of "protoproedros".