ΔE 12.7, fair: the same colour family, but not a straight swap. Dune Shadow is more saturated, cooler than Basilisk Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Dune Shadow is more saturated, cooler than Basilisk Brown.
The same difference applies the other way round: Basilisk Brown 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 Basilisk Brown on the colour wheel See Dune Shadow on the colour wheel
All matches: Basilisk Brown equivalents · Dune Shadow equivalents