MAC Blackground is a very warm-toned, dark black with a pearl finish. It is a discontinued eyeshadow that retails for $23.00 and contains 0.17 oz.
MAC Blackground Pro Longwear Paint Pot ($18.50 for 0.17 oz.) is described as a "black grey with multicolour." It's a soft, medium black with brow undertones and a very soft smattering of silver shimmer. Urban Decay Spell has more multi-colored shimmer and is a powder product. NARS Empire is similar in color and is also a cream product. MAC Backlit is less warm-toned and has multi-colored shimmer.
FURTHER READING: Formula Overview, which is a detailed review of the range as a whole.
A highly pigmented, long-wearing, blendable eye primer and/or cream shadow – M·A·C Pro Longwear Paint Pot goes on creamy and dries to an intense, vibrant finish that lasts for 24 hours. The innovative second skin-like creamy shadow formula blends smoothly over lids and creates seamless, buildable coverage without looking heavy or cakey. Its superior colour purity stays true and will not streak or crease. Pro Longwear Paint Pot can be mixed with other products, like M·A·C shadows and liners.