Imagine the wonder when this masterpiece was discovered. It was October 24, 1831 and in the Casa del Fauno in Pompeii the splendid mosaic with the battle of Issus emerged. The famous battle saw the victory of Alexander the Great against the Persian king Darius III. But think that it is a copy. Let me explain. The Romans of the IV-III century BC copied a large Hellenistic painting, making it however with the mosaic technique. And the artists who created it did so in a virtuosic way, using very small tesserae, with a maximum side of 3 mm. This allowed the imitation of painting, avoiding that discontinuity in the chromatic and linear fabric that we usually see in mosaics. Going into the detail of the scene, the battle sees as the protagonist Alexander on horseback who pierces a Persian dignitary with a long spear. On the royal chariot, King Darius turns towards him with a gesture of pain. Observe how the mosaic artists have managed to create chiaroscuro effects and reflections with great skill. You can see it well in the shiny coat of the two horses in the foreground. Few colors appear in the image, white, black, various ranges of ocher, browns and reds, which are those traditionally used by the Greek painters of the classical period. But it doesn't stop there. We are surprised by the surprising spatial and perspective glimpse . In fact, we know that the ancient Greeks had already discovered the foreshortening, or the representation in perspective of a body in an oblique position with respect to the background plane. In addition to the horizontal trend, we find many elements that make us understand the sense of depth. The horse in the center of the scene, the weapons abandoned on the ground, the spears in the background that bend towards the figure of Alexander. They are all coherent spatial solutions . To all this are added the finest details such as the sumptuously decorated robes or the reflections and glimmers of the weapons. Or even the possessed or terrified gazes of men and animals. Hence it is natural to ask ourselves what sublime levels the ancients had managed to reach with the pictorial technique. In any case, the overall effect is that of an enveloping sense of movement, of battle noises, of the crash of weapons and the neighing of horses.