All the Side Quests in Legend of Dragoon are optional, since they have no effect on the main storyline. However, they usually don't take too long, and some of the rewards can be found nowhere else in the game. I recommend trying all of them for fun and some cool prizes.
SIDEQUESTS Location Mission Reward Limestone Cave Catch the rabbit Poison Guard Bale Talk to painting girl Painting of Lavitz Marshland Eliminate all enemies invading the 7th Fort Experience and Gold Lohan Get Gold DS from guy who sold you the Water Bottle Kongol's Dragoon Spirit Donau Free Lynn and return to Donau immediately Kate's Boquet Queen Fury The Vegetable Julian - Chop chop! (Try using all the characters) 1 piece of Gold Evergreen Forest Defeat Kamuy Gold Reward Fort Magrad Defeat Polter Armor Dart's strongest sword, the Soul Eater Vellweb Defeat the four undead Dragoons in tower Respective Dragoon Stones Flanvel Defeat Faust (see Stardust) Phantom Shield Mayfil Defeat the three Dragon Spirits Down Burst, Frozen Jet, Destone Amulet