Quest Giver: Gwen
Reward: 1x Star Bangle
After the Nuisance in the Factory side quest, the Junk Dealer will inform you of a large Drake that also needs killing, the Cerulean Drake. Head towards the train station where you’ll run into Gwen’s heated argument with two Shinra guards. She’ll ask you to get a needed key card in order to get to the drake and points you back to the abandoned factory.
At the factory, return to the area as indicated by the map marker (where you found that Fire Materia in the prior quest). To the left of the the fate doorway, you’ll find a stack of breakable boxes. Break them with Cloud’s sword to find the key inside.
With the key in hand, head to the last warehouse, where you’ll find a locked door with a control next to it. Use the key card on it (press ) to face the Drake. This fiend is similar to the Lesser Drakes in strategy and wind magic weakness, but has ice magic abilities that’ll slow your attacks and movement. Once killed, return to Gwen to complete the quest.