ΔE 13.8, fair: the same colour family, but not a straight swap. Red Iron Oxide is a little lighter, more muted, warmer than Blood for the Blood God.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Red Iron Oxide is a little lighter, more muted, warmer than Blood for the Blood God.
The same difference applies the other way round: Blood for the Blood God is a little darker, more saturated, cooler.
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 Blood for the Blood God on the colour wheel See Red Iron Oxide on the colour wheel
All matches: Blood for the Blood God equivalents · Red Iron Oxide equivalents