ΔE 15.0, loose: different enough that you should pick on purpose. Hexwraith Flame is a little darker, more saturated, cooler than Matt Goblin Green. They are different kinds of paint: AMMO by Mig Matt Goblin Green is an ink, glaze or transparent paint and Citadel Hexwraith Flame is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Hexwraith Flame is a little darker, more saturated, cooler than Matt Goblin Green. They are different kinds of paint.
The same difference applies the other way round: Matt Goblin Green is a little lighter, 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 Matt Goblin Green on the colour wheel See Hexwraith Flame on the colour wheel
All matches: Matt Goblin Green equivalents · Hexwraith Flame equivalents