Thief isn't really a class in ffxiv, but you can still make one. You just need the following abilities:
Archer: (Hide, Flee)
Chameleon: Blend in with your surroundings, consuming TP to reduce enmity.
Quickstride: Quicken your stride, increasing movement speed.
Pugilist: (Steal, Perfect Dodge?, Sneak Attack)
Steal: Rifle through an enemy's belongings, stealing a random item. Chances of success increases with stealth.
Featherfoot: Tread lightly, increasing evasion. Effect fades after evading an attack.
Blindside: Strike from an enemy’s rear, increasing attack power by half of your dexterity.
Lancer: (Trick Attack, Sneak Attack)
Collusion: Employ deception, transferring the enmity generated by your next successful attack to an ally positioned between you and your enemy.
Overrun (Weaponskill): Close in on an enemy, increasing TP and dealing piercing damage. Can only be executed when the target is unaware of your presence.
The only thing missing now is a dagger wielding class.
Edited, Jul 11th 2010 5:51am by Dodoy