ΔE 25.7, loose: different enough that you should pick on purpose. Rocket Green is noticeably darker, much more muted, warmer than Goblin Green.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Rocket Green is noticeably darker, much more muted, warmer than Goblin Green.
The same difference applies the other way round: Goblin Green is noticeably lighter, much more saturated, 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 Goblin Green on the colour wheel See Rocket Green on the colour wheel
All matches: Goblin Green equivalents · Rocket Green equivalents