Zarusoba is a cold type soba dish.
It is similar to Mori Soba.
Zaru soba is topped with shreded Nori.
Mori soba is topped with nothing.
Both of soba noodle and dipping sauce are same in Zaru soba and Mori soba.
In my case, I prefer Zarusoba.
Because I think Nori is good for soba.
Usually Zaru soba is served on rounded plate, Mori soba is served on squarish plate.
Long ago, Dipping sauces were different in Zaru soba and Mori soba.