Paradox Cohort is an Event summoned through the use of the Ancient Watch at any time. It is defeated once a certain number of enemies are killed. During the event, an army of paradox creatures invade the world. This takes place all throughout the surface, not only in the middle of the world, with unique enemies appearing in certain Biomes.
The Titan Soul will appear after the invasion is summoned and will float in the air. Violeum will spawn 4 times during the event. After the progress bar gets to 98%. the Titan Soul will transform to Paradox Titan. After the Titan is killed, the invasion will end. You can't end the invasion without killing the boss.