ΔE 12.0, fair: the same colour family, but not a straight swap. Magnus the Red is a little darker, more muted, cooler than Eye of Terror.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Magnus the Red is a little darker, more muted, cooler than Eye of Terror.
The same difference applies the other way round: Eye of Terror is a little lighter, more saturated, 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 Eye of Terror on the colour wheel See Magnus the Red on the colour wheel
All matches: Eye of Terror equivalents · Magnus the Red equivalents