Hemisphere collider?

I can get this working in blender and even heckin Roblox but Unity does not want to cooperate.

Is it possible to have a half sphere collider?

Convex does not seem to work because the rounded side of the half sphere does not roll smoothly.

Thank you!

Unity uses PhysX for 3d physics. PhysX does not have a primitive hemisphere collider. Unity actually implements all the primitive colliders that physX provides (sphere, capsule, box) as well as the more complex colliders like MeshColliders and heightmap colliders (for the terrain). A sphere is the most simplest collider as it’s very easy to describe mathematically. However a hemisphere is quite complex to describe mathematically. Also a hemisphere is a rather unusual shape. Your only options is using a convex mesh collider or you use a different physics engine. Though I have never heard of a physics engine that has a native primitive hemisphere collider.