ΔE 6.6, close: similar, with a visible difference side by side. Ruby Red is more saturated than Molten Lava. They are different kinds of paint: Army Painter Molten Lava is an opaque base/layer paint and Green Stuff World Ruby Red is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Ruby Red is more saturated than Molten Lava. They are different kinds of paint.
The same difference applies the other way round: Molten Lava is 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 Molten Lava on the colour wheel See Ruby Red on the colour wheel
All matches: Molten Lava equivalents · Ruby Red equivalents