The world needs a hero - but what hero will you be? Creating a character in City of Heroes is an exciting process that presents you with the opportunity to harness your imagination. You get to choose your character's "Archetype", "Power Sets" and have the flexibility to craft a unique personal costume.
An Archetype is a character-class. Each has their own strengths and weaknesses and differing play-styles. Your choices are: Tanker, Blaster, Scrapper, Defender, and Controller. This is the single most important choice you will have to make about your hero.
Tanker: Out of all the Archetypes in City of Heroes (and even City of Villains!) nobody can withstand the enemy's attacks as well as a Tanker. They do moderate damage but their real strength is taking the damage dealt by the bad guys and protecting the more fragile Archetypes.
Blaster: This is the damage-dealing specialist. Not only do Blasters do a lot of damage, they can do it to a lot of enemies. Their Area-of-Effect damage powers can reduce the health of the target mobs heavily. Yet, their only defence is a strong offence.
Scrapper: The Scrapper is the close-range combat specialist. They do impressive amounts of damage and have reasonable defences. Solo they are very powerful. In teams of course their abilities are worth having but they will not replace the need for a Tanker and Blaster.
Defender: Healing and buffing are so necessary for a team that hardly anyone would form one without a Defender, given the choice. Controllers share some of the Power Sets from this Archetype but a dedicated Defender is highly desirable. Defenders share some similar powers from the sets of the Blaster and can hold their own in a fight fairly well if they have to. Many of their most useful powers are not useable on the self, however, making the Defender more effective in a team than solo.
Controller: Controllers are an interesting Archetype that can incapacitate the enemies and make sure they don't fight back effectively. This can mean putting a whole group to sleep, or hold a boss that would otherwise be difficult to beat. To cap this off they also get some Defender powers as their Secondary Power Set. The real trade off is that they struggle to do direct damage BUT with an inherent ability that does extra damage to a foe already held they can maximise the few damage powers they have.
So... next come Power Sets. There are just too many to list. This is where you choose whether your powers do (for example) fire damage, or ice, or darkness etc. Each Archetype has a Primary and Secondary Power-Set and you can mix them so that if your Primary set is one type like fire you can still have ice as your Secondary set. The different options allow for many character builds. Most offensive power-sets have an additional effect on top of the damage they deal. Energy sets stun the opponent, Ice sets slow them, Fire sets burn for additional damage, Archery sets have extra accuracy... each set has its own advantages.
So, what does the hero actually need? There has to be a balance between what you would like to create and what you would like to play as. You won't be able to build one character that really does it all, you will always need the help of other team members. Yes, a priority is creating someone that you can imagine playing as but with a little experimentation you could try another role that you find enjoyable. Still, there will be characters every now and then that you create who have such a great concept that you will over-look the actual numbers and instead find your own place in a team. Then again, you might find an archetype that you enjoy and decide to try different power-sets, a few times even, to get exactly what you want to play on your way to Level 50.
Every team needs at least some melee fighting ability. Tankers and Scrappers can intercept the enemy and get their attention before they get past them to the more fragile heroes who will typically be closer to the rear of the group. This is referred to as keeping "Aggro" and this is where Tankers in particular excel. With their every attack, they build Aggro. On top of that, most good Tankers will take the power "Taunt" that will immediately do just that and force the affected group of enemies to attack the Tanker and ignore other targets. Tankers are not a true damage-dealing Archetype but their steady output of attacks will help beat down the bosses and clear out minions. Scrappers are very powerful solo, having a mix of very strong offense and effective defense. They are less specialised than other Archetypes but in a team they can handle most of the aggro they generate and help the Tanker while dealing a large amount of damage. This gives the team its durability.
Someone needs to be doing the damage. Blasters are the specialists here as long as they have Tankers and Scrappers to hide behind. High damage is boosted even more by the availability of Area-of-Effect powers which can blast away whole groups at once. A smart Blaster will stay out of the range of the majority of bad guys only ducking in occasionally for a melee attack perhaps. Blasters are sadly without much in the way of defenses and can die quickly before a healer can even get to them. As they do this, Scrappers can be putting out serious damage; while Defenders will be able to make use of their attacks, which although they do less damage, can still be helpful. Tankers do less damage but can take the hits back they get - this means a Tanker can in fact kill most foes before they get killed, or better yet, with some help they can kill their foe and take all the Aggro from the rest of the bad guys.
Perhaps the hardest aspect of a team to find is Healing and Support. Defenders and Controllers are the two classes that can have the most trouble solo so perhaps are a little less popular to play, though extremely popular to have in a team. With healing and buffing, Tankers become nearly un-killable and if they fill their role properly they will save the rest of the team from dying, and the same powers will make even Blasters more survivable (though the Blaster that needs constant healing is taking away attention from the Tankers and Scrappers that are actually meant to be at the front of the fight.) Some interesting powers are available to Defenders that recharge slowly but can but the whole group. If you are in a team and a Defender says "Gather for..." then the power is ready and it's best to get close to be in range for the power. Controllers also have healing powers but they trade the Defender's damage-dealing powers for Control powers.
Teams will often call out over broadcast chat in large zones that they need a "Tanker" or "Healer". When they say they want a healer then just about anyone with an Area-of-Effect healing power could apply, and if you are a dedicated Defender you can watch as they jump for joy when you join their team. Tankers are the second thing most teams have trouble finding but a team can certainly do with more than one even. As a Blaster you might get a few invites when the team needs damage and if the team already has its tanking and healing a Scrapper or two certainly won't be under appreciated.
It is common for players to try many different characters and over time most will build a good understanding of each person's role in a team. Of course, just playing one character to a high-enough level to see what experienced teams do will also help greatly. Either way, City of Heroes has a lot of options for the creative gamer, and the community to make teams enjoyable. Get in there, get your cape on and show those villains what a real hero is made of!