Ptolemy is a saint that follows the orders he is given. When the four bronze saints arrive along with Athena at the Sanctuary, he is there to greet them in disguise. At first he tells them what will be awaiting them inside the 12 temples. But as soon as they come into the vicinity of the Aries temple he reveals himself and attacks them with a shower of phantom arrows. However, the Bronze Saints realize they are all illusions and Seiya easily defeats him. There is yet only one golden real arrow that he shot, which hits Saori right in the chest. Before he dies, he tells them they must reach Pope Ares in less than 12 Hours so that he can remove the arrow before it pierces Saori's heart (Source: Saint Seiya Wikia)