NOTE: Please ignore the forum trolls. If they had have any worthwhile input it would have been put in this guide. Remember: trolls thrive on the misery of others; your disappointment makes trolls happy.
The Assassin
In Perfect World, the Assassin class cannot be described as a sub-category of any other class (such as Blade Master). Though there can be claims of similarity, there are simply too many of them for too many different classes to label Assassin to be similar to a single one.
Why be an Assassin?
As mentioned above, the Assassin is a specialist and not a fighter. The Assassin's skill set is designed for a more technical and indirect way of fighting. Many of the skills that the Assassin has possesses an ulterior motive and are meant to work in conjunction with one another. While the skills themselves are self explanatory, when combined in a specific order, they can overcome many obstacles that other classes face constantly.
Is Assassin for me?
Through careful observation, it turns out that Assassin is not for everyone. Many found Assassin far too difficult to play and run into issues such as dying constantly and worrying about the constant low health. Others seem to go for a more direct approach with using strong, direct attack skills; however, they still run into minor tads of trouble, such as having gaps in their attacks that allow the opponent to retaliate harshly.
The Assassin class are built for methodical thinkers. The ideology is to plan ahead, strike fast, strike quickly, don't give the opponent the chance to think. If you like direct fighting, being able to take hits, and not having to think while you're swinging your weapon away, this is not the class for you.
Common Misconceptions and Explanation
Well, let's start off by restating that the Assassin is a specialist, not a fighter. The fighter classes in PWI optimizes their DPS (damage per second) by using normal attacks. While this is a viable option early on for Assassins, it becomes a major detriment to the Assassin later until it reaches the late levels (level 65-75 and above). One of the skills Assassins get at mid levels increases their damage base dramatically (30 Attack Levels, meaning you'll always do 30% more damage), but at a massive cost. Once this skill is maxed, your attack speed get shot down 100%. Yes, this is correct, your normal attacks literally stop at 0.59 or lower. So, this clearly indicates that Assassins were meant to methodically pin down opponents with skill spamming unless you happen to have a Speed Focus (which will be explained in a bit).
The Assassin class's strongest defense is within it's offense and adaptability. Though it is offense oriented, it's still not as capable in direct combat as Archers, Blade Masters, and Barbarians. Archers have defensive capabilities of Range; Blade Masters with Heavy Armor, Defense Buffs, Self Healing, and Pure Damage oriented skills; Barbarians with Heavy Armor, High HP, Defense Oriented Skills, and High Damage weapons. Unfortunately, the Assassin's weapons are among the weakest of all the physical damage oriented classes, Light Armor without the benefits of Ranged Combat, Weak and Limited Self defense skills, and is by no means a ranged class. However, this changes when Assassin reaches later levels when they can Spark Burst+ endlessly.
Assassin skills are very indirect in nature. Instead of overwhelming the opponent with sheer power, they set the pace of combat in their favor. By limiting what the opponent can do (such as making them unable to move, cast, run, chase, self-destruct nearby, attack quickly, attack accurately, so on, and so forth), the Assassin makes it so the opponent cannot function and fight under normal conditions. Assassins are meant to fight debuffed opponents while buffed, this is their edge.
Assassin Stat Builds
The Assassin class revolves around Light Armor and Daggers. The dagger's damage comes from the dexterity stat. Dexterity influences accuracy, evasion, and critical hits. There are both pros and cons to each build, but it is highly recommended to stick to one of the three builds.
Pure Dex Build
Every Level: 1 Str, 4 Dex
Pros: Maintain highest damage ratio and critical rate.
Cons: Rather fragile.
Hybrid Build
Every Even Level: 1 Str, 4 Dex
Every Odd Level: 1 Str, 1 Vit, 3 Dex
Pros: Fair attack ratio, survive a few more hits
Cons: Each fight will take just a little longer to win.
Vitality Build
Every Level: 1 Str, 1 Vit, 3 Dex
Pros: Most HP of the 3 and survive some harsh blows.
Cons: Lower damage and critical ratio, losing 1% critical every 20 levels compared to Pure Dex build.
Note: In order to maintain up to date weapons and light armor, 1 Str and 3 Dex is absolutely vital.
Assassin Focuses
The Assassin class is very varied in terms of gameplay styles, thus why many arguments and debates drag on in conversations about skills and their uses. Each skill actually has it's own uses and efficiency. The longer you play Assassin, the more you realize the effectiveness of each skill when used properly and efficiently. There will always be debates on whether or not a skill is effective, but you must first question which focus you're aiming for first before questioning others. Simply because one skill does not appeal to you does not mean it will not appeal to another.
Assault Focus
Those with this mindset will mostly be MP heavy with the mindset that every little bit of damage adds up to the speed of the kill and it is the speed of the kill that determines how much damage is taken per monster. With little belief in defense, those with this focus will concentrate more on Chi and Skill Damage. Added effects will seem only a bonus to the kill to those with this focus. Channel and Cast will also play a major role to their decision making. Though skilling should slow down around level 65+.
Defensive Focus
Those with this mindset will not be as MP heavy as those with an Assault Focus. Attack Skills are only secondary to one's own survival. Those with this belief will concentrate more of their Spirit Points into skills that minimizes the damage one takes. Attack is crucial to those with this focus, but too many will seem like a burden than helpful. With this focus, damage is not important, thus if offensive skills do not meet a certain criteria they will view it as useless. Though, defensive countermeasures don't mean as much around level 65+.
PvP Focus
Those with this mindset will be the most range oriented of them all. Their focus aims towards punishing opposition from all angles and punish them as quickly as possible. They minimize Spirit consumption by only aiming for critical attack and defense skills, leaving the rest for mobility and range. Those with this focus will be proficient in PvP, but the least efficient in PvE when compared to the other focuses. This is a focus you would want when you decide to slow down on levels and concentrate more on PvP.
Speed Focus
The rarest breed of them all, those with speed focus. Those with this mindset are minimalists in terms of skills and concentrate their spirit more into chi building skills only. Their aim is to optimize spark eruption efficiency and to kill quickly with as little MP consumed as possible. Instead of focusing on skills, they aim more towards gear that up their attack speed and critical rate. Movement is a plus, but not essential to those with this mentality. This is only recommended to those who have alternative characters over level 90 with much coin (in the hundred millions range) to throw around to optimize this build. One of the best viable PvE options post-70.
