Gale Slash is one of Dunban's physical Arts in Xenoblade Chronicles. It is an attack that inflicts damage and Bleed on the target. It is also part of several two-art combo attacks. Worldly Slash, Tempest Kick, and Electric Gutbuster all have bonus effects if used immediately after Gale Slash.
Advanced art books are only available from enemy drops. For any enemies listed with a 0% drop rate, the item can only be obtained using Yoink!, Riki's Talent art.