How to mix to material with mix node

I have 2 different material (Ocean & Snow) from PBR material Addon. I want to mix both the nodes so that they combine each other smoothly. I have a node with green and white mix and same way i want combine both nodes to achieve a smooth result. Any suggestion or help how can mix both the Materials. Why there is a black edge line seen. Thanks

combine nodes.blend (2.3 MB)

Mix shader node. Works like the MixRGB but for BSDF (shaders)

and what about the black line seen like edge

That’s a geo problem from adding a plane under another mesh that’s been deformed, so it’s causing a shadow. You can try disabling shadows on the plane, but you might still get ambient occlusion. You could disable that, but that has other side effects. You can raise the ocean plane, lower the mountain plane, or try moving all the edge verticies of the mountain plane to the ocean plane with snapping set to face.

Come to think of it, I would probably select all the edge of the mountain plane, scale, z 0. Then move them all together to the ocean plane.