ΔE 15.2, loose: different enough that you should pick on purpose. Dark Reaper is more muted, cooler than Scaly Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Dark Reaper is more muted, cooler than Scaly Green.
The same difference applies the other way round: Scaly Green is more saturated, 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 Scaly Green on the colour wheel See Dark Reaper on the colour wheel
All matches: Scaly Green equivalents · Dark Reaper equivalents