东方希莲船 ~ Ultimate Fatal Octopus

"东方希莲船 ~ Ultimate Fatal Octopus" is a fan-made Touhou Project STG game that features a battle against a UFO controlled by the alien passersby, Sirena. The game includes two playable characters, four shot types, and four difficulty levels. It also offers an upgraded danmaku engine, Steam Leaderboard with anti-cheat, and auto-dodging function if you have Project Beril installed. The game has only one stage with a UFO system recreated from Touhou Undefined Fantastic Object.