The Xel'Naga Artifact Shard is a medium-sized, asymmetrical fragment of an ancient alien artifact, glowing with a soft, pulsating blue luminescence. Its surface is smooth yet intricately engraved with alien hieroglyphs that emit a faint glow, suggesting a mysterious power source. The shard's edges are jagged, as if broken from a larger structure, with a crystalline interior that refracts light, creating an ethereal effect.