This is Rhombosa, a variant of Dominosa, using rhombi on a triangular grid instead of dominoes on a square grid.

The idea came to me after seeing Jonah Ostroff, who has made quite a few isometric puzzles, make a joke about a certain “uniqueness deduction” in Dominosa. It’s an interesting mathematical question as to which reasonable hexagon sizes can be used with full sets, and a surprisingly human-solvable one to figure out which sizes of regular hexagon would work with a “standard” triangular-number domino set.

I do think 3×3×2 and the 1-6 domino set might be a bit small for this puzzle type because this shape means that deductions can trigger a lot of other deductions, but this one is nice as an example if nothing else.