This newly crowned crustacean is the second-story boss of , and beating her is no easy feat. Her fight opens up the rest of the map; until you beat her, you're confined to the starting area and its surrounding caves and crevices.
You'll quickly run out of things to do here, so beating Magista is a surefire way to find new places and shells to put on. Magista is the self-appointed Duchess of Slacktide, the castle near Kril's tide pool.
When his home is repossessed, he's told that it's due to some new tax laws that the new leadership has put into place, and he needs to take it up with the Duchess if he wants leniency.
The Loan Shark points you in the direction of the castle, and so that's where you head. You fight Nephro on the way, but once you reach Magista, you'll need to be ready; she's a toughie, though developer Aggro Crab has a solution for you if you find the fight too tricky.
When you arrive at Slacktide after retrieving Magista's pearl as she asked you to, you'll notice things have changed since you left.