Two Become One

The Two Become One is a Keychain for Sora's, Roxas's, and Xion's Keyblades that was introduced in Kingdom Hearts II Final Mix. The Two Become One represents Roxas, as borne out by its obtainment, appearance, and ability, Light & Darkness, which makes it easier for Sora to obtain Final Form.

Design
Two Become One is one of the more sword-like Keyblades, possessing a curved, notched blade that bears a slight resemblance to Soul Eater and Way to the Dawn, with a noticeably sharp edge. Its color scheme is derived from a fusion of Roxas's Oathkeeper & Oblivion Keychains, and the handle is composed of the same checkerboard pattern on Roxas's wristband. The Keyblade's design is also covered with references to Roxas's Nobody nature; the usual Nobody thorns make up the teeth and rainguard, which is black and rounded. The chain links are heavily stylized versions of the Nobody Emblem, and the full Nobody Emblem adorns the hilt. The token itself is Roxas's Nobody-thorn charm.

The Keyblade's name refers to Sora and Roxas merging together into one.

Gameplay
In Kingdom Hearts 358/2 Days, this Keyblade's ground combo begins with a thrust forward, followed by a diagonal vertical strike from the right side, and continues with a lightning-fast array consisting of a horizontal slash left, the same slash right, and a vertical downward slash and ending with a jump back and a rushing diagonal spinning slash. Players can change the combo and end it after the first upward slash by pressing ; this will trigger a jump into the air and a slightly angled spinning slash. The aerial combo is a rush forward and two downward spinning slashes from either side. These combos are the same as those used when Roxas wields Oathkeeper in the battle with Riku.