Dumb overpowered yeah

How

Yes

It only warps away that part of your body that the shuriken makes contact with and not even half of it. Kaguya's arm was just cut in half. I think a sword would be better.

*throws shurikens on the ground*

Earth literally fucking disentigrates

There's literally just a small hole in the ground now.

It could kill anyone that isn't immortal.

*COUGH COUGH* KAGUYA *COUGH*

Its a good idea a shuriken that kamuis someone on impact but like @Sy6up said a sword could be far better

Kamui sword would be overpowered, but Kamui shuriken is only good when a Susanoo is using it