Thief isn’t so much a thief as it is an assassin. Nothing about it is very thief-like, except for two job ability's called Steal (It has a five-minute cool-down timer and rarely ever steals anything, If it does it usually sucks anyway.) and Mug which can steal a nice amount of Gil from NM's and such. On the other hand, Thief also has Sneak Attack and Trick Attack. Those are very assassin-esque, and basically all that Thief ever uses. Thief is one of the most survivable jobs in the entire game. It’s a support-role job that never takes hate. If you do for any reason take hate, you have the most evasion in the game, and since you’re going to be subbing Ninja for almost all your career, you have Utsusemi. If all that fails, you have Perfect Dodge and Flee too. Not to mention Hide. If you don’t