ΔE 11.8, fair: the same colour family, but not a straight swap. Night Lords Blue is more saturated, warmer than Marine Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Night Lords Blue is more saturated, warmer than Marine Blue.
The same difference applies the other way round: Marine Blue is more muted, cooler.
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 Marine Blue on the colour wheel See Night Lords Blue on the colour wheel
All matches: Marine Blue equivalents · Night Lords Blue equivalents