ΔE 12.4, fair: the same colour family, but not a straight swap. Bad Bruise is a little lighter, more saturated than The Darkness.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Bad Bruise is a little lighter, more saturated than The Darkness.
The same difference applies the other way round: The Darkness is a little darker, more muted.
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 The Darkness on the colour wheel See Bad Bruise on the colour wheel
All matches: The Darkness equivalents · Bad Bruise equivalents