Found inside a small cave located in one of the last sections of Somnus Reef. Explore the whole level until reaching the ocean's surface after defeating Rusalka. In the first big surface room (inhabited by infinite Saint Elmos and an Edimmu), head to the leftmost part and enter the cave to find him. Absorb the Torpor glyph in order to free him.
- "Hide and Seek!"
- "Show Me the Owl!"
- "Can't Catch Me!"
- Objective: Try to catch Serge with your surroundings blackened in less than 30 seconds.
- Reward: Green Drops
- At first, Serge will be reluctant on speaking with Shanoa, as he will be very worried about his mother's whereabouts. Rescuing her will take all his sorrows away and let him become the playful kid he always was, allowing him to give quests to Shanoa.
- During the first quest, "Hide and Seek!", Serge will always be in a random barrel every time the quest is initiated, this requires speed and luck from the player, as there is no single way to determine where he is.
- During the third quest, "Can't Catch Me!", only Shanoa's surroundings will become pitch black. The second screen of the Nintendo DS (the one that shows the current map/enemy information) will still be visible, making the quest a bit easier as Serge will always be just on the roof of the building near where the player starts.
- GameFAQs.com - Quest Guide by Darth Nemesis.