Mattsu, Yamma and Moburi - The Naval Treasure and Riddle Island
Mattsu to Yanma to Moburi-san 2: Suigun Otakara to Nazotoki no Shimajima · マッツとヤンマとモブリさん2 ―水軍お宝と謎解きの島々―
Synopsis
The sequel focuses on the islands west of the city. (Source: Anime News Network)
Source: OTHER