ΔE 15.8, loose: different enough that you should pick on purpose. Hydra Green is much more muted, cooler than Lupercal Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Hydra Green is much more muted, cooler than Lupercal Green.
The same difference applies the other way round: Lupercal Green is much 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 Lupercal Green on the colour wheel See Hydra Green on the colour wheel
All matches: Lupercal Green equivalents · Hydra Green equivalents