ΔE 14.0, fair: the same colour family, but not a straight swap. Ulthuan Grey is a little darker, more muted than Orc Blood.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Ulthuan Grey is a little darker, more muted than Orc Blood.
The same difference applies the other way round: Orc Blood is a little lighter, more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Orc Blood on the colour wheel See Ulthuan Grey on the colour wheel
All matches: Orc Blood equivalents · Ulthuan Grey equivalents