Mythical Orange vs Ruby Red

How close are they?

ΔE 8.7, close: similar, with a visible difference side by side. Ruby Red is more saturated than Mythical Orange. They are different kinds of paint: Army Painter Mythical Orange 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.

Can I use Ruby Red instead of Mythical Orange?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Ruby Red is more saturated than Mythical Orange. They are different kinds of paint.

Can I use Mythical Orange instead of Ruby Red?

The same difference applies the other way round: Mythical Orange 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.