Coffin dancers 2.0 (For Cusstom campaign.)

You point at someone and mutter some obscure words. Then we're you pointed coffin dancers aperar and one tagget of your choice gets stuck in a coffin. The dancers are nonexistent but can be seen, we're as the coffin is a normal object. The target takes 3d10 Phsycic damage. On there turn they can make a strength throw and on a sucses they end the spell and land prone on the ground. On a fail the spell continues. On your turn as a bonus action you can have the coffin dancers continue dancing and the target takes 1d8 Phsycic damage and you can move them upto 10 ft.