Shadow Thorn vs Terror Blue-Grey

How close are they?

ΔE 14.9, fair: the same colour family, but not a straight swap. Terror Blue-Grey is a little lighter, much more muted than Shadow Thorn.

Can I use Terror Blue-Grey instead of Shadow Thorn?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Terror Blue-Grey is a little lighter, much more muted than Shadow Thorn.

Can I use Shadow Thorn instead of Terror Blue-Grey?

The same difference applies the other way round: Shadow Thorn is a little darker, much 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.