A specialized, water-based paint manufactured by Games Workshop for painting plastic, metal, and resin miniatures.
Dries to a completely smooth, flat matte finish that eliminates unwanted glare and shine. A non-toxic, water-based acrylic formula. As a "Layer" paint, it features a lower pigment density and higher fluidity compared to "Base" paints.
A balanced, rich mid-to-dark pure royal blue. It is slightly cooler and more vibrant than other options like Alaitoc Blue. Designed to flow smoothly over base coats without blocking out fine sculpted textures. It is ideal for edge highlighting, broad highlights on cloth robes, and clean panel lines. 
For optimal results, you should transfer the paint to a palette and lightly thin it down with water or acrylic medium. Multiple thin applications will yield a much smoother color gradient than one thick layer.
It is universally used as the primary mid-tone layer when painting Ultramarines power armor (layered directly over a Macragge Blue base and subsequent Drakenhof Nightshade wash). It is also a staple for painting the blue robes of Stormcast Eternals and Collegiate Arcane wizards.