Hello again !
I had a lot of issues with FastCast by @EtiTheSpirit , and this one pretty simple to understand.
When I start firing under the line of the sky, the casts are going down and don’t make their way to the direction. Heres a sketch (don’t minde my skills)
This is not an FC error. This has to do with how Roblox handles hit detection positions on the skybox.
The intent of a skybox click is for the distance of the projection to be “infinite” (emphasis on the quotation marks). This causes a different result than when you click on a nearby target.
There’s a few ways to fix this and each is different depending on the game. I won’t elaborate since this is something you can research yourself, but its worth it to note.