A unique achievement of Kush’s civilization is the Meroitic script. The Meroitic script, which was developed in the Kingdom of Kush, is a writing system that was used to write the Meroitic language. It is considered a significant achievement as it reflects the distinct cultural identity of the Kushite civilization, separate from that of Ancient Egypt, which used hieroglyphics.
While the other elements mentioned (hieroglyphics, papyrus, preparation for the afterlife) are also associated with ancient Egyptian culture, the Meroitic script is specifically tied to the uniqueness of Kush's achievements.