This trophy is obtained for completion of the ninth main story mission and is thus an unmissable part of the progression through the game.
**Minor Mission Spoilers Follow**
Upon visiting Lucain to show him the black runestones, he directs you seek a hermit in the Lost Woods. First you must visit the castle for a letter of introduction. Upon travel to the Magic Gate you find it is sealed and need to backtrack to the Adventurer's Guild. Now the Stables are unlocked and you can use that (for a fee - lvl+1 * 30) to travel to the 'Lost Woods' (dungeon level 9). Alternately you can use the gate for free but the destination is random (not advised). In the Lost Woods you will shortly reach the hermit and get the research, but the rest of the level will be spent trying to get *out* of the woods. If you successfully complete your boat trip (avoid the whirlpools and defeat the fish before they land in your boat), you will eventually reach a crystal cave (look for destructable crystals worth tons of points). If your boat gets destroyed you will miss the crystal cave and instead fight a few more waves of enemies. Whichever way you go, you finally reach a really bad-ass Gazer (basically a classic D&D Beholder) boss. You will finally be awarded the trophy in the results screen in the Dragon Haven Inn while receiving the Ancient Dragon Research (right before the 'Appraise' screen).