Occultist Cloak vs Viking Grey

How close are they?

ΔE 8.9, close: similar, with a visible difference side by side. Viking Grey is a little darker, cooler than Occultist Cloak.

Can I use Viking Grey instead of Occultist Cloak?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Viking Grey is a little darker, cooler than Occultist Cloak.

Can I use Occultist Cloak instead of Viking Grey?

The same difference applies the other way round: Occultist Cloak is a little lighter, 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.