Shelldiver is a 2025 cozy incremental game developed and published by Gagonfe. It follows a senior turtle who dives underwater to catch jellyfish, sell them in a small shop, and upgrade gear for deeper exploration. Players discover new biomes, improve equipment, help the local turtle community, and steadily expand their undersea routine. The game stands out for its relaxing progression, charming aquatic theme, and light idle-style management on PC.