The Domino Tiles block spans U+1F030–U+1F09F, 112 codepoints in Plane 1 (Supplementary Multilingual Plane). 100 are assigned in Unicode 16.0; the other 12 are reserved for future characters.
All of its characters have the script value Common: they are shared across writing systems rather than tied to one.
By general category: 100 other symbols (So).
The first 100 arrived in Unicode 5.1 (2008).
Because it lies outside the BMP, every character here takes four bytes in UTF-8 and a surrogate pair in UTF-16.