ΔE 13.8, fair: the same colour family, but not a straight swap. Dark Magenta is noticeably lighter, more muted than Blood Thorn.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Dark Magenta is noticeably lighter, more muted than Blood Thorn.
The same difference applies the other way round: Blood Thorn is noticeably darker, 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 Blood Thorn on the colour wheel See Dark Magenta on the colour wheel
All matches: Blood Thorn equivalents · Dark Magenta equivalents