In this set you have 4 paints selected by Seth Apter:

Midnight - an opaque dark blue with green tones
Buff - an opaque lovely off white cool neutral
Terracotta - a transluscent rusty orange
Mahogany - a semi-opaque, cool dark red-brown

As you have versions of the primary colours, plus buff to lighten, you can create with set a wealth of other rustic, interesting colours. Very useful, and VERY Seth Apter!