How to hide part of a mesh when it is under your landscape

So what I’m looking to do is hide my mesh when under my landscape

Which may seem a bit pointless? As you’d think you’d never see it - but my project has this ‘mining’ aspect to it - where the floor is a voxel system and you can dig chunks out of it to create tunnels - like this;

So you can imagine static meshes on top of the landscape is fine but what I would like to do is hide meshes under the landscape

So here is an example of my problem;

I want to see the top of the sphere and hide the bottom of the sphere

So is there a way to create maybe a material that would be shown on top, detects the intersection point from the landscape and then changes the opacity of the material when the Z point is below the landscapes? Something like that

Or open to hearing if there’s a different approach to achieving my goal