The Astral Blast is a Keychain for Roxas's and Xion's Keyblades that appears in Kingdom Hearts 358/2 Days. It can be upgraded to the Astral Blast+.
The Astral Blast has a black handle with a silver spike in its pommel and a peculiar guard. The left half of the guard is blue with a small, silver section at its bottom, rectangular, and connects to both ends of the handle, while the right half is silver, curves outward slightly, and does not connect to the bottom of the handle. Its shaft is blue on its left half and yellow on its right half. The head of the blade is yellow and forms a large hook that curves to the left. Its teeth are comprised by three curved spikes lining the outer edge of the hook. The Keychain token is a blue and yellow five-pointed star with a small, circular gap in its center. In addition, the Astral Blast is a palette swap of the Abyssal Tide Keyblade.
The ground combo starts with a thrust, then a diagonal upward slash from the right leg, a vertical downward slash, a hilt thrust, and finishes with another diagonal vertical slash from the left leg. The combo can be extended by hitting in which case you will jump into the air and do a spinning slash with the Keyblade above your head. The aerial combo is the same as the Darker Than Dark Keyblade.
 See also