How to project texture onto sphere mask

Hello,

I was wondering if it was possible to mask the sphere mask result with a texture alpha?

I was following this tutorial to make a blob shadow, and I thought I could go one step further to make a texture based shadow, but lerping or multiplying with a texture alpha doesn’t work with this setup.

Blob Shadow Tutorial

The end result I’m trying to achieve is a drop shadow similar to what Mario has in the newer installments, especially Odyssey.