If you become a thief, you'll be able to steal your enemy's belongings. You will also be able to tell how much treasure is in the vicinity.
--Description in Dragon Quest VII
The Thief (盗賊, Touzoku) is a class in the Dragon Quest series. It was not available in the original Famicom version of Dragon Quest III, being added later to the Super Famicom version of the game as a bonus class.
Thieves have high agility and balanced physical stats with decent attack and defensive power making them nimble melee combatants. What makes them vital to a party is their ability to steal items from the last monster defeated at the end of a fight. Outside of dungeons and caves they possess abilities such as Eye for Distance that allow the player to locate villages and nearby towns.
Thief is one of the prerequisites for the Ranger vocation (along with Monster Master and Merchant). Their auto-stealing rate improves with each Rank increase, doubling at Rank 8. This means a party of thieves will have an 8 times higher chance to nab an item.
Attacks the enemy and has a chance of stealing its item
0
Usefulness
The Thief's best skill is Nose for Treasure which allows treasure hunters to know how much treasure is left on a particular floor. As for hybrid skills, Thief Hit, the hybrid skill of a Warrior and a Thief, is probably one of the useful hybrid skills to learn as it has the chance of taking one item from a monster regardless of whether or not it is defeated. However, the default stealing rate is quite low. To this end, the character must have a high rank in the vocation to steal reliably.
Regarding evolution, the Thief can combine a mastered Shepherd class to become a Monster Masher. They will learn all sorts of breath skills and have a chance at taming monsters for the Monster Park. The Thief can also combine a mastered Shepherd class to become a Pirate. The Pirate learns sea based attacks which is useful as most monsters, save the aquatic ones, don't have resistance to these skills. Plus they are cost effective.
The Thief vocation is available at the start of the game and has the unique skillset "Acquisitivess". Thieves can also use skill points to learn Sword, Knife, Claw, and Fisticuffs skills. Their Coup-de-Grace is "Itemized Kill," which guarantees treasure dropped after the battle.