ΔE 25.5, loose: different enough that you should pick on purpose. Rotten Pus is noticeably lighter, much more saturated, cooler than Gryph-Hound Orange.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 25). Rotten Pus is noticeably lighter, much more saturated, cooler than Gryph-Hound Orange.
The same difference applies the other way round: Gryph-Hound Orange is noticeably darker, much more muted, 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 Gryph-Hound Orange on the colour wheel See Rotten Pus on the colour wheel
All matches: Gryph-Hound Orange equivalents · Rotten Pus equivalents