ΔE 10.4, fair: the same colour family, but not a straight swap. Titan Buff is a little lighter, more muted, warmer than Screaming Skull. They are different kinds of paint: Citadel Screaming Skull is an opaque base/layer paint and Golden Titan Buff is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Titan Buff is a little lighter, more muted, warmer than Screaming Skull. They are different kinds of paint.
The same difference applies the other way round: Screaming Skull 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 Screaming Skull on the colour wheel See Titan Buff on the colour wheel
All matches: Screaming Skull equivalents · Titan Buff equivalents