Solving Request 66, known as The Sea's Legend, stands out as one of the most intriguing puzzles in Pokemon Legends Arceus. Rather than offering straightforward map markers, this quest requires trainers to decipher an ancient riddle tied to three specific water-type creatures. By preparing your party and timing your actions correctly, you can successfully uncover the secret cave and add rare mythical Pokemon to your Hisui Pokedex.
Gathering the Required Pokemon
Before attempting to trigger the quest's secret event, you must catch three specific Pokemon to carry in your party. The required creatures are Buizel, Mantyke, and Overqwil. While Buizel and Mantyke are easily found in the Cobalt Coastlands, acquiring Overqwil requires evolving a Hisuian Qwilfish.
To evolve Hisuian Qwilfish into Overqwil, you must have it use the move Barb Barrage in Strong Style 20 times in battle. Once all three Pokemon are in your active team, head over to the Coastlands Camp in the Cobalt Coastlands. This setup is essential because the game checks your party composition before triggering the legendary event.
Passing Through the Ocean Gate
With Buizel, Mantyke, and Overqwil ready in your party, rest at the camp until evening falls over the sea. Next, mount Basculegion and ride out across the water toward the giant two-pointed rock arch standing near Sand's Reach. Pass directly through the center of the rock formation while the evening sun sets.
If performed correctly, a dialogue prompt will appear on the screen describing a distant cry and a shifting boulder. This notification signals that the hidden entrance to Seaside Hollow has finally been unlocked on the coast. You can now proceed to the final destination without worrying about time restrictions.
Exploring Seaside Hollow
Head toward the northern side of Veilstone Cape to locate the entrance to Seaside Hollow. Before stepping inside the cave, it is strongly recommended to manually save your game. Saving beforehand prevents you from accidentally losing your chance to capture the legendary targets if your team faints.
Inside the cave, you will encounter one Manaphy alongside three Phione floating together. These Pokemon spawn with protective water shields that block incoming Pokeballs during combat. Throw a Pokeball or partner Pokemon twice to shatter their shields and initiate a standard battle.
Catching Manaphy and Completing the Request
Focus your strategy on capturing Manaphy first, as catching it is mandatory to clear the request. The surrounding Phione can also be caught or defeated during the battle without failing the quest. Using status moves like Sleep or Paralysis will make catching these mythical Pokemon significantly easier.
After securing Manaphy, return to Jubilife Village and report your discoveries to Professor Laventon. He will mark Request 66 as complete and reward your efforts with three valuable Comet Shards. Completing this legendary storyline provides a satisfying payoff to one of Hisui's greatest mysteries.