ΔE 10.2, fair: the same colour family, but not a straight swap. Cavalry Brown is more saturated, cooler than Black Rose Immortal.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Cavalry Brown is more saturated, cooler than Black Rose Immortal.
The same difference applies the other way round: Black Rose Immortal is more muted, warmer.
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 Black Rose Immortal on the colour wheel See Cavalry Brown on the colour wheel
All matches: Black Rose Immortal equivalents · Cavalry Brown equivalents