ΔE 13.2, fair: the same colour family, but not a straight swap. Deep Green is a little lighter, more saturated, warmer than Serpent Shadow.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Deep Green is a little lighter, more saturated, warmer than Serpent Shadow.
The same difference applies the other way round: Serpent Shadow is a little darker, 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 Serpent Shadow on the colour wheel See Deep Green on the colour wheel
All matches: Serpent Shadow equivalents · Deep Green equivalents