Thief

The Thief is a fast paced melee class focusing on damage avoidance and high rate of attack.

To become a thief talk to the Dye Trader to get the quest. The Thief Class Test in which you will be given a goal to collect 2 Antlion mandibles obtain then return to the Dye Trader to turn it and receive your class.

Name	Effect	Cost/Cooldown	Requirement
Critical Wounds	Adds Critical Chance 1%, 3%, 4%, 7%, 10%, 13%, 16%, 19%, 22%, 25%	Passive	Flexibility Lvl 5
Flexibility	Increases Dodge Rate +2.5% per level, up to 25% Decreases Defence Approx -1% per level, down to -10%	Passive	None
Master of Blades*	Increases Attack Speed for Swords +3% per level, up to 30% Increases Damage for Swords +1.5% per level, up to 15%	Passive	Flexibility Lvl 5
Snatch	Increases Gather Range for loot.	Passive	Steal Lvl 7
Poisonous Blade	Attacks cause Poison Debuff 5 Seconds / level.	2 seconds, no cost.	None
Steal*	Steal from nearby monsters. 17.5% Success, +7.5% per level, up to 85% chance.	30 Mana cost at Lvl 1 57 Mana cost at LvL 10	Flexibility Lvl 3
Hide	Invisibility Buff* 3 Seconds / level.	30 Mana at level 1, no cooldown.	Steal Lvl 5
Dodge*	Invincibility 0.4 Seconds/Level, up to 2 seconds.	1 Second	None

1: Steal appears to cause the target to drop items as though it died. It does work against mini bosses, but does work against minibosses, such as the Wyvern and Ice Golem, allowing for rapid collection of difficult to acquire resources. Testing indicates it may be possible for multiple nearby targets to drop items at once.

2: Hide, as the standard invisibility potion, does not hide clothes, and does not deter monsters.

3: Yes, Dodge does in fact grant up to 2 seconds of invincibility - the same absolute, flashing, invincibility as happens when you've been hit - with a cooldown of 1 second and no mana cost. A thief with 5 levels in Dodge is unkillable for as long as you use the skill. This is likely a bug.

4: Despite the description mentioning "Swords", for the purposes of this skill, this includes Scythes and Greatswords, as well as Fish-type weapons. Bug: If a Sword-type weapon is active in the hotbar and it is used from the inventory screen, applies to apply to other Melee-type weapons too. Likewise, if a non-Sword weapon is active, then any sword used from the inventory is at its base damage and speed.

Final Level Status Bonus

Status	Bonus
Strength	+7
Vitality	+3
Dexterity	+7
Charisma	+0
Agility	+14
Intelligence	+5
Luck	+6
Wisdom	+0

Skill Ratings

Meh Tier - Actively bad to increase, fairly bad to even ''use''.

Poisonous Blade - Poison. Low effect, widely resisted, and easily replicated with Stingers and Bottled Water if you really needed it, which you don't.

Hide - Unless you're a hardcore PVPer, Invisibility potions are useless gimmicks. Use them instead if you must.

The Other Tier - Every other skill.

Because the Thief only needs 49 skill points to max out its other, useful abilities, so long as you avoid the above pitfalls, you'll max these naturally, but they're listed and rated anyway for completeness.

Critical Wounds - A good, solid skill for any class that likes to damage things, and the thief is no exception.

Flexibility - The best way to mitigate damage, and a keystone to many thief skills. Max it as soon as possible, the defense penalty is trivial compared to the chance for 100% damage mitigation. With a total of 102 Agility at level 130, you'll easily hit the 75% dodge cap.

Master of Blades - The thief's primary means of boosting their damage output, and a great one at that. A 30% Attack Speed increase and 15% damage increase means it offers a 49.5% overall boost in damage output, but you'll suffer against high Defence enemies. Also of note is that even the Terra Blade can only be boosted to about 3 projectiles per second, meaning that your Attack Speed upgrades won't really add to your ranged DPS.

Snatch - Simple, solid utility skill. Fully maxed, your pickup range is around 6 blocks away. Not a high priority, considering how easy it is to just "walk four blocks closer" in most situations, but not bad when you're building.

Steal - Another neat little skill, an 85% chance to essentially double the drop from a non-boss mob is nothing to sneeze at, particularly if you can set up a rare mob in a spot where you can steal multiple times in a row. If you advance to thief early, you may want to pick this up sooner, rather than later, to accelerate your progression, but raw damage and damage prevention may be more worthwhile otherwise.

Dodge - Even if it wasn't bugged and actually cost MP, Dodge would be a great skill, 2 seconds of absolute immunity to everything at the cost of mana the thief wasn't using anyway? Perfect for when you're cornered, expecting to get hit, or need to deal with a boss's murder move.

What Build?

Thieves are pretty simple to build, enough Agility to max dodge (if you have an Almighty Stick, this figure may decrease as you level up), max everything except Poisonous Blade and Hide. From there, it's your choice whether to go for Strength or Dexterity (probably strength for the overall higher damage output). In cases of bosses who can one-shot kill you (assuming you're not just standing still spamming Dodge the whole fight), you may wish to invest some of your remaining stat points into Vitality (which should more or less allow you to survive at least one hit from any single target).

Late game, you're going to want to get the Terra Blade and never look back, but keep an eye out for earlier projectile Swords (In normal mode the Ice Blade, Enchanted Sword and Starfury) to add some vital ranged utility to your weapons without sacrificing a good proportion of your damage. With such a rapid attack speed, Cobalt or Palladium swords with their autoswing might work out better than even Titanium until you can move onto Chlorophyte and Excalibur.

Updated from Arendeth here is some updated info of theif for N Terriaria 6 i have gathered

Poison bomb: Generates a poisonius field around you. Uses deathweed in order to cause the poisoning. info:not worth points does no damage to enemies it seems when i tested it note lasts single second or so uses 1 deathweed from inventory ~30 second cooldown mana cost 60

Toss Knives:toss knifes in the mouse direction. Damage is (sic) 60 percent plus 4% per level. caps at 10 points info: note not worth the points since can have same range with chain type melee weapon~15 second cooldown

Evasion:Description:Jumps back to avoid being hit. points max 1

Evasion mastery: Description:Increases evasion by 10 percent with 2 percent evasion added per skill level. max points 10

Grapple:tosses the enemy to the other side by using your weapon damage is 80 percent        info:~2 - 3 second cooldown can hit friendlies beware recommended to put at least one point in acts as a teleport same as warriors just different requirements to get

Double attack: Description:Adds chance of double attacking when attacking normally. Every level adds 8 percent chance of double attacking. Only valid to melee weapons like swords. (swing-type or is it melee type that only required?)   type:sustain/toggle info: might not work for throw type weapons but dps should be similar after swing type weapons are peared with sword mastery and dual wield mastery. Recommended build for skill points: 10 Double attack (can turn on and switch later on when out of active use slots since is a sustain that costs nothing), 1 evasion, 10 evasion mastery, 9 grapple (will still be useful after get next class and poison bomb has been tested to be useless and not worth points Recommended class to take after maxed to level 30 (does not take long if use dungeon to level it) slashed weapon speced warrior Recommended Goblin for pierce racial that grants 10 percent pierce or the cat race. Stats max vit of 20 to not die in single hit later on and equal mix of str and agility (make sure to get heart orbs maxed as soon as possible)

as warrior might take sword experience 10 Heavy slash 5 Dual wield mastery 10 counter attack 5  or if dont want heavy slash 

 sword experience 10 Dual wield mastery 10 counter attack 10