Team roles

There are five different roles in a team:

Tank

The Tank's job is to protect your teammates, especially the squishy back rank. The main way of accomplishing this is to make the enemy focus on you as a target and continue to attack you. The second way is to use a Crowd Control ability to prevent them from reaching and/or attacking your teammates.

A tank is also usually the initiator of combat. If he isn't the initiator then he is usually the first one in after initiation occurs. A tank's initiation usually involves moving quickly to the enemy forces and disabling as many as possible momentarily.

There are two general categories of tank: Burst Tank and Endurance Tank.
A Burst Tank is able to take a lot of damage over a short period of time and then either dies or flees combat. This type of tank is very useful for initiation if you or the enemy team has a lot of burst damage as he will be able to negate or reduce most of it. If the battle needs to take longer, however, the tank will become useless. Burst tanks can be identified by their having a large health pool, strong defensive abilities with long cooldowns and either no healing abilities or weak and/or inconvenient healing abilities. The following are typical Burst Tanks: Amumu, Cho'Gath, Alistar.

An Endurance Tank is able to withstand lots of damage over a long period of time. They won't have as great of defensive potential as a Burst Tank but they make up for it with long-term survivability. If the enemy has a lot of burst damage then the endurance tank will be useless. However if they focus on crowd control and pushing power then an Endurance Tank will shine. Endurance tanks may be able to stand in the fray for long periods of time or may have to duck out of battle momentarily to refuel before heading back in moments later. Endurance Tanks can be identified by having low cooldown defensive abilities and a high health regeneration or strong self-healing abilities. The following are typical Endurance Tanks: Shen, Gragas, Singed.

Requirements:
A tank requires two things:
1) Exceptional Survivability
2) A degree of threat or an attention grabbing mechanism

A tank also benefits from the following:
1) high mobility
2) a way to rescue teammates
3) a way to initiate combat
4) slow/stun/positioning moves that can keep enemies close by

Tactics
The following are typical ways for a tank to grab attention:
1) Position: A tank should be the first one in battle and the closest to the enemy. Often a tank becomes the target simply because he is the only target in range, with the rest of the team safely behind him shooting from afar.
2) Feigning Vulnerability: When the tank's health bar is low he seems like more of a target, even if he would still have more health than an ally. Tanks with surprise defensive moves, like most Burst Tanks, should wait until their health bar drops before activating them. That way they will appear vulnerable even if they are not and grab more attention.
3) Being Loud: Tanks often have loud, flashy moves. Even if they deal no damage these moves grab attention and the enemy will have a difficult time ignoring it.
4) Be a Threat: Tanks don't normally deal a whole lot of damage but they can still be a threat - a player just needs to use his champion's power efficiently. The main way for a tank to be a threat is by going after the enemy Carry. Carries usually have very low survivability and so doing significant damage to them will be much easier. By threatening the carry not only are you making the enemy notice you but you are also helping the team do appropriate damage.
5) Pulling the enemy in: If an enemy attempts to walk by you should try to 'pull him in' if you have a way to do so. This could mean stunning, slowing, taunting, repositioning or any other manner of Crowd Control to keep the enemy on you and not your allies. This works best against melee champions but could also work against long ranged ones.

Tanks must think of their team first and themselves second. Tanks don't require as much money as carries do and so should feed their carries as many kills as possible and be willing to fork out gold for Wards to help out the team as a whole. If a battle turns sour the tank should be the last one out, even if it means death, in order to keep the rest of his team safe. If possible a tank should always sacrifice his life to make sure an ally gets away and should discourage his team from coming back for him. Don't let this keep you underfed, however. Tanks have the hardest time farming and can easily suffer from being underleveled if due attention isn't payed. Make sure your team stays defensive when you go and feed because without a tank the whole team is more vulnerable.

Tanks must be bold and brazen. When combat is engaged, get in there right away and make as much noise as possible. Make sure you know the difference between an initiation and a harass, however. A Harass is when an ally goes and makes a quick attack to get on the enemy's nerves and get them to initiate prematurely. A initiation is the beginning of a full-blown attack. If your ally is harassing and you run in, you will just be sacrificing your life for nothing. If it's an initiation and you don't run in then it could either be a missed opportunity or your whole team could die because you weren't up front protecting them.

Off-Tank

An Off-Tank (Offensive Tank)'s main job is to pursue and add close-up pressure to the enemy carries, especially Ranged Carries. Like a Tank an Off-Tank must emphasize Survivability but an Off-Tank must also be able to deal significant amounts of damage.

An Off-Tank's second job is to grab the slack that a Tank leaves over and take all the focus that falls off of him. If the main Tank should die or be forced to run away then the Off-Tank must be able to step into his shoes and be the main attention-grabber.

An Off-Tank may have crowd control abilities but the main way he grabs attention is by dealing Damage. All of this damage should be focussed on the vulnerable targets in the enemy team, especially if that means wading through the enemy's front line and pulling them back with you.

Off-Tanks are also divided into Burst and Endurance, like with Main Tanks. They are also divided into Physical and Magical for the way they deal damage.
Examples:
Dr. Mundo is a Physical Endurance Tank. Blitzcrank is a Physical Burst Tank. Nunu is a Magical Burst Tank, Vladimir is a Magical Endurance Tank.

Units with heavy lifesteal can also be classified as Off-Tanks. Those would be: Warwick, Irelia, Fiddlesticks.

Requirements:
1) High Survivability
2) Moderate damage output

An Off-Tank also benefits from the following:
3) High Manoeverability
4) Stun/Slow Effects

Tactics:
Tanks have the highest independence of the game. They are the most capable in 1v1 fights as they have the best balance between survivability and damage output - thus they make the best Junglers throughout the whole game. Off-Tanks have medium priority when if comes to kills and farming - more than tanks and support but less than the carries. Off-Tanks can also get fed quite easily. Be careful because having a fed Off-Tank may seem like a good idea and may be quite effective in the early and mid game, but come late game if the off-tank gets all the kills and the carry gets none then the team will suffer. and the tides will turn.

Off-Tanks generally don't have initiation moves or have very poor ones. It is possible for them to initiate simply by running into the middle of the frey but Off-Tanks will generally only come into battle after it has already been initiated - sometimes right after.

The first thing an off-tank should do in battle is move throught to the back line, destroying the enemy ranged units. This will have one of four effects:
1) The Off-Tank will succeed in killing the ranged units, throwing the battle in your favour
2) The Off-Tank will chase off the enemy ranged units or otherwise keep them occupied while your team continues pressing forwards
3) The Off-Tank will cause the front line to shrink back and deal with him, allowing the rest of his team safer access to the enemy back line and distracting the enemy from your team's carries
4) The Off-Tank will be targetted and killed, drawing the enemy's resources momentarily and allowing your own team the opportunity to deal damage to more vulnerable targets

If any enemy unit flees the battle the off-tank has the right to pursue a short distance and go for the kill on his own. No other unit should leave a team fight to do so. This is because the Off-Tank will both be able to deal damage and survive should the enemy champion turn around with a surprise heal+ignite+super burst whereas other units, like Carries, would be decimated from that kind of turn around.

As mentioned above, if the team's tank falls it is the off-tank's job to take his place. The off-tank should continue going after the carries if possible but should also be aware of his position in relation to his team and the enemy and be ready to intercept any unit going towards his teammates. An off-tank in this situation should play more defensively and should not leave battle to chase a fleeing enemy.

Melee Carry

Carries are usually divided by into the Physical and Magical categories as Carries and Mages. Functionally, however, these two categories are more or less the same, with the exception that Physical carries focus more on auto-attacks and strict damage dealing while magical carries focus more on abilities and often have a form of crowd control or area damage.

Functionally, the main distinction among carries is Melee vs. Ranged and thus this guide will focus on that as the distinction.

The job of a Melee Carry is to deal massive amounts of damage. They have no other possible role than that and should not attempt to multitask other roles. They should not initiate combat, rescue teammates or chase fleeing enemies unless they are 110% certain they can do so without dying in the process.

Melee Carries need to survive at all costs. If it means fleeing battle while it is still going on then so be it. They should not run into battle with half a bar of health unless the enemy team is in worse shape or they have a surprise rescue mechanism (which they usually don't).

As with the tanking types, Melee Carries have two subcategories: Burst and Endurance. Here their role is defined by the type of damage they produce. Burst Carries will have massive damage output with high cooldowns on their abilities. Endurance Carries will have high damage output which can be sustained almost indefinitely through auto-attacks or low cooldown abilities. There are also Magical, Physical and Hybrid type carries.

Requirements:
- High Damage Output
- Medium Survivability
- Short-ranged Teleport/Leap (even if it's just Flash)

Melee Carries also benefit from the following:
- High Mobility
- Single target stuns/slows
- Lifesteal/Spell Vamp

Tactics:
When a team fight occurs the Melee Carry will be constantly ducking in and out of battle. Burst Carries especially should simply pop into battle, throw down all of their abilities, then immediately retreat and stay their until their cooldowns refresh. Endurance carries should remain in the fray for a while longer, leaving as soon as they pick up even the slightest hint of enemy aggro.

Burst Carries should be the second ones in, right after the Tank. This way they can lay down their first wave of abilities immediately and have them refreshed before the encounter is completed. If a Burst Carry waits too long before engaging then they will have less volleys of attacks to throw at the enemy.

Endurance Carries should wait until the Off-Tank is also present before engaging the enemy. This way the Endurance Carry will be able to stave off aggro for a little while longer and will have more time before they are forced to retreat. They'll also be sure that they miss the first volley of enemy Burst Damage.

After combat is underway keep ducking in and out as necessary to ensure survival and maximum damage output. If any single enemy flees let him run... chasing is a good way to get caught and killed. Instead work on whittling down any enemies who remain in the battle - even if it's just the tank.

Between team fights a Melee Carry should remain busy. There are three things they could be doing:
1) Hunting down solitary Range Carries who stray too far from their protection
2) Clearing neutrals from the jungle
3) Farming lanes in controlled areas

A Melee Carry should NEVER harass opponents at a tower. They are ineffective at doing so and will just be wasting their time.

Melee Physical Carries are also the prime candidates for backdooring, when the situation arises.


Ranged Carry

A ranged carry's main job is to deal massive amounts of damage. A secondary job is as supplimentary Crowd Control, especially with a Mage type. The third job of a ranged carry is drawing out and over-extending enemy champions. The third job is automatic just by being alive and so functionally works as 'be a threat but stay alive'.

Ranged Carries, as with their Melee Counterparts, must survive at all costs. If this means fleeing battle halfway through then so be it. 9 times out of 10, however, a ranged carry can run away far enough to get the enemy to stop chasing them then come back and keep attacking.

With a good tank, Ranged Carries should be able to focus solely on purchasing offensive items or hybrid items. If the tank isn't doing his job then some heavier defensive items may be warranted.

Ranged Carries are also occasionally initiators and they make great harassers.

All the sub-distinctions of Melee Carries (Burst/Endurance/AP/AD/Hybrid) also apply to Ranged Carries.

Requirements:
- High Damage Output
- High Attack/Spell Range

Ranged Carries also benefit from the following:
- High Mobility
- Crowd Control abilities

Tactics:
When a team fight occurs the Ranged Carry will always be the last one in a fight and will stay as far back as possible. The Ranged Carry should always, always, always stay behind the Tank, even if it means his only contribution is attacking the enemy tank. Attention should be payed, however, and when the opportunity arises to walk forwards and do damage to the enemy squishies it should be done immediately.

Burst Carries have a bit more leeway when it comes to the Tank Line rule... when they know that the enemy team is occupied they can duck forwards past their tank for a second to get off their abilities, then run back to safety and auto-attack who they can (or run away) as their abilities refresh. Endurance Carries have to place Survivability at a much higher priority, however, and remain in a safe positioon as much as possible.

Between team fights a Ranged Carry should remain busy. There are three things they could be doing:
1) Harassing an enemy tower with the support of a tank,
2) Farming lanes in controlled areas
3) Clearing neutrals from the jungle
4) Hang back at your tower and wait for the next team fight.

A ranged carry should as much as possible stay with the rest of the team. This is important for all champions, but squishy ranged ones especially.

Support

Support champions are the most versatile and individualized of them all. They basically fill any kind of miscellaneous role other than straight Damage Dealing and Damage Taking.

There are three main types of Support Champions: (1) Buffers, (2) Enervators, (3) Assassins

Buffers are primarily about boosting your allied teammates' effectiveness, either by healing them, shielding them or boosting one or more of their stats. Examples are: Janna, Soraka, Sona.

Enervators are primarily about reducing your enemy champions' effectiveness, either by cursing or crowd controlling them. Sometimes Enervators are nicknamed 'failed mages' because almost any Mage champion can also be built as Support by emphasizing Cooldown Reduction and Mana Regen instead of Ability Power. Examples are: Morgana, Lux, Malzahar.

Assassins are primarily about establishing Map Control by either roaming the jungle and killing solitary champions, frequently ganking or otherwise scaring the enemy team into sticking together and not straying into the jungle. Assassins can often take the role of Carry as well but they should be classified as Support as their play style is based on sideways thinking and guerilla tactics as opposed to straight combat. Examples are: Teemo, Twitch, Eve.

Support Champions can usually fill several different roles and may be difficult to classify. Looking at which ability you consider your 'bread and butter', however, will aid you in classifying yourself to some extent.

When it comes to Items, Buffers and Enervators should mainly focus on Aura items which benefit the team as a whole. If the enemy is targetting you then purchasing Defensive Items (especially Aegis of the Legion) is also a smart move. The only flat AP item such a support champion should purchase is Mejai's Soulstealer, which is extremely effective on Support Champions as they get lots of assists and generally stay far out of harms way.

Assassins should build themselves for straight damage dealing as if they were a carry.

Requirements:
- None. Well, it really depends on the type of Support Champion.

Tactics:
In team fights, all Support Champions should stay out of harm's way as much as possible. Buffers should stay close to the allies they need to buff, Enervators should be close enough to the enemy champions they need to enervate and Assassins should hang in the shadows until they find the ideal place and time to strike.

Buffers and Enervators should play extremely generously and, like with Tanks, should avoid getting kills when another ally can take it. Assassins, however, should attempt to steal kills whenever possible, even if your team starts to hate you.

In all roles remember that you are a Support Champion. Buffers and Enervators should never go alone and even when Assassins go solo they alway need to remember to 'check in' with their team once in a while.

Support Champions all need strong Map Awareness, Assassins because they need to know where they should be and the rest because it benefits the team and Support Champions are the most able to multi-task this function. All are prime candidates for taking the Clairvoyance spell and purchasing Wards (note I said 'and' not 'or'... one isn't a replacement for the other).

Already read it somewhere else, but for those who haven't read it yet, do it.
It's really helpfull!