The Radical Treatise is an ornate, predominantly gold lexicon with roughly oval-shaped covers. The spine is decorated by a red diamond, as well as two white, pentagonal shapes, one above and one below the diamond. The middle of each cover is decorated by a red spike with gold edges shaped like those on the Nobody sigil. There is a black arm-like shape on either side of the base of the spike.
When using the Radical Treatise, Zexion's ground combo finisher (without pressing after the first hit) will be a short-range claw coming out from his lexicon, dealing damage to enemies that it hits. When using the combo, Zexion attacks using the usual slam, then an upper slam, then an aerial slam, and then he makes the Treatise "eat" his enemy. To wield the Radical Treatise, Zexion must have the Pandora Gear attached.