ΔE 14.3, fair: the same colour family, but not a straight swap. Malignant Green is a little lighter, much more saturated than Matt Bile Green. They are different kinds of paint: AMMO by Mig Matt Bile Green is an ink, glaze or transparent paint and Army Painter Malignant Green is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Malignant Green is a little lighter, much more saturated than Matt Bile Green. They are different kinds of paint.
The same difference applies the other way round: Matt Bile Green is a little darker, much more muted.
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 Bile Green on the colour wheel See Malignant Green on the colour wheel
All matches: Matt Bile Green equivalents · Malignant Green equivalents