ΔE 21.6, loose: different enough that you should pick on purpose. Orc Skin is noticeably lighter, more saturated, warmer than Hulky Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Orc Skin is noticeably lighter, more saturated, warmer than Hulky Green.
The same difference applies the other way round: Hulky 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 Hulky Green on the colour wheel See Orc Skin on the colour wheel
All matches: Hulky Green equivalents · Orc Skin equivalents