Thunder Storm vs Corvus Black

How close are they?

ΔE 6.9, close: similar, with a visible difference side by side. Corvus Black is more muted than Thunder Storm.

Can I use Corvus Black instead of Thunder Storm?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Corvus Black is more muted than Thunder Storm.

Can I use Thunder Storm instead of Corvus Black?

The same difference applies the other way round: Thunder Storm is more saturated.

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.