ΔE 10.4, fair: the same colour family, but not a straight swap. Gray Green is a little darker, cooler than Terminatus Stone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Gray Green is a little darker, cooler than Terminatus Stone.
The same difference applies the other way round: Terminatus Stone is a little lighter, 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 Terminatus Stone on the colour wheel See Gray Green on the colour wheel
All matches: Terminatus Stone equivalents · Gray Green equivalents