How Can I Use More Than 16 Textures on a Material?

I am trying to make a landscape material with multiple biomes and need to use more than 16 textures in my main material. Packing grayscale images into a single image won’t help as I am planning to add more diffuse textures. How can I get it to work with more textures on a single landscape?

Select your additional textures in the material editor and set their Sampler Source to Wrap.

Do I want to do this with all my textures?

Just the additional textures(16+) should do.

Thanks, it works.