ΔE 14.0, fair: the same colour family, but not a straight swap. Warboss Green is noticeably lighter, more saturated, warmer than Fern Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Warboss Green is noticeably lighter, more saturated, warmer than Fern Green.
The same difference applies the other way round: Fern Green is noticeably 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 Fern Green on the colour wheel See Warboss Green on the colour wheel
All matches: Fern Green equivalents · Warboss Green equivalents