Gwarhar Lagoon is a coastal area in Mario & Luigi: Superstar Saga.
Gwarhar Lagoon consists of several beaches, and the ocean floor can be accessed from here. A variation of Gritty Goombas are found in Gwarhar Lagoon, and so are a more powerful version of the Troopea called the Elite Troopea. An enemy called the ???? can be found here as well.
Mario and Luigi first visit this area after the S.S. Chuckola is propelled out of Teehee Valley and sinks to the bottom of the ocean. The Mario Bros. can enhance their hand powers here by going to a relaxation center called the Relaxation Room, run by the Jellyfish Sisters. A crab called Hermie III resides here, and he is in possession of the first Beanstar piece. Later, the Bros. can find a Starkiss called Spangle, who wants to stand on top of a stage. Conveniently, Hermie's shell is the perfect stage for Spangle, and Spangle is the perfect replacement for the Beanstar. Hermie will reward them with the Souful Bros. Badge if they do this.