ΔE 8.3, close: similar, with a visible difference side by side. Miskatonic Grey is a little lighter than Grey Seer.
Usually, if you are not matching paint already on the model. Close match (ΔE 8). Miskatonic Grey is a little lighter than Grey Seer.
The same difference applies the other way round: Grey Seer is a little darker.
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 Grey Seer on the colour wheel See Miskatonic Grey on the colour wheel
All matches: Grey Seer equivalents · Miskatonic Grey equivalents