ΔE 22.1, loose: different enough that you should pick on purpose. Runic Purple is noticeably darker, more saturated, warmer than Gorgon Hide.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Runic Purple is noticeably darker, more saturated, warmer than Gorgon Hide.
The same difference applies the other way round: Gorgon Hide is noticeably lighter, 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 Gorgon Hide on the colour wheel See Runic Purple on the colour wheel
All matches: Gorgon Hide equivalents · Runic Purple equivalents