ΔE 12.5, fair: the same colour family, but not a straight swap. Deep Sky is much more muted than Night Lords Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Deep Sky is much more muted than Night Lords Blue.
The same difference applies the other way round: Night Lords Blue is much 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 Night Lords Blue on the colour wheel See Deep Sky on the colour wheel
All matches: Night Lords Blue equivalents · Deep Sky equivalents