Bony Spikes vs Tyrant Skull

How close are they?

ΔE 9.8, close: similar, with a visible difference side by side. Tyrant Skull is a little darker, more saturated, cooler than Bony Spikes.

Can I use Tyrant Skull instead of Bony Spikes?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Tyrant Skull is a little darker, more saturated, cooler than Bony Spikes.

Can I use Bony Spikes instead of Tyrant Skull?

The same difference applies the other way round: Bony Spikes is a little lighter, more muted, 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.