ΔE 8.4, close: similar, with a visible difference side by side. The Fang is a little lighter, cooler than Ultramarine Blue.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). The Fang is a little lighter, cooler than Ultramarine Blue.
The same difference applies the other way round: Ultramarine Blue is a little darker, 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 Ultramarine Blue on the colour wheel See The Fang on the colour wheel
All matches: Ultramarine Blue equivalents · The Fang equivalents