黑月Extend is a side-scrolling fighting game developed by Beijing Yixin Huyu Technology Co. Ltd. The game takes place in a world where Black Moons have returned and threaten to invade the world. As a chosen protector, you are tasked to fight off the Black Moons and protect the world from destruction.

The game's storyline is set in a parallel universe where the Black Moons have taken over the world. You play as a member of the Black Moon Academy and must unravel the mystery behind the disappearance of the witches and stop the Black Moons from invading the world again. The game features a compelling storyline, challenging battles, and impressive graphics.

Overall, 黑月Extend is an engaging side-scrolling fighting game with an intriguing storyline and captivating gameplay that will keep you hooked for hours.