ΔE 11.4, fair: the same colour family, but not a straight swap. Creamy Ivory is more saturated than Tyrant Skull.
Can I use Creamy Ivory instead of Tyrant Skull?
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Creamy Ivory is more saturated than Tyrant Skull.
Can I use Tyrant Skull instead of Creamy Ivory?
The same difference applies the other way round: Tyrant Skull is more muted.
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.