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.
Equipping the Rapidus Fioglyph will allow Shanoa to easily inspect all barrels in the village within the given time limit.
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.