This skill is often equipped onto Swordmasters and Snipers wielding weapons with high Critical rates, essentially granting them a 100% critical hit rate with a fairly accurate Hit Rate.
In Awakening, Gamble decreases its user's Hit rate by 5 points and increases his/her Critical rate by 10. It is learned by Level 10 Barbarians.
In Fates, the skill (Roundhouse in the Japanese version) now has an equal trade off, with it now having -10 Hit rate and +10 Critical rate. It is a Nohrian skill, being learned by Fighters at Level 10 or higher.