Caitlyn Build Guide by Luther3000
This build has been archived and is for historical display only.
PLEASE NOTE: This build has been archived by the author. They are no longer supporting nor updating this build and it may have become outdated. As such, voting and commenting have been disabled and it no longer appears in regular search results.
Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Threats to Caitlyn with this build
|Twitch||Twitch simply can't handle Caitlyn's harass and pushing power. He has no way to harass back or clear waves and even his damage is lower in early game. He only has a chance if he can force a fight once he has items.|
| Masteries |
| Items |
| Mid Game |
Hi friends, I'm a veteran LoL player who has been playing the game and following the competitive scene for over four years. I main AD Carries/Marksmen with about 1600 normal games played. I don't play much ranked, but last season I was Platinum V for solo queue and Platinum III with my ranked 5s team.
I bought Caitlyn way back in season 1 and she has always been one of my favorite champions in the game. I've written one previous guide which was also for Caitlyn, but it became very outdated and to be honest I wasn't very good at that time. Watching Doublelift playing Caitlyn at IPL5 was the inspiration for me to start playing Caitlyn again and to start over with this guide.
In other words I like to think that I know what I'm talking about.
If there is any term you do not understand, please check the LoL Terminology before asking.
|||||| Caitlyn is a ranged Attack Damage Carry AKA Marksman, a role that specializes in building massive amounts of damage and annihilating enemies from a distance.
Caitlyn's strengths compared to other ADCs are her considerably superior range; the average ADC has a range of 550 whereas Caitlyn's is 650, allowing you to hit your opponent without receiving damage in return. Caitlyn's abilities combined with this range allow you incredible poking and zoning potential and make her a very safe, strong laning pick that has no losing matchups. Caitlyn has been considered a relatively strong ADC for virtually her entire existence.
On the downside, her mid game is somewhat weak and her aggressive pushing/zoning style of laning invites ganks from the enemy team. She's also not very good in a straight up fight to the death, so if you fall too far behind on Caitlyn you could find the game snowballing against you.
|||||Armour seals are virtually required for laning against ranged AD opponents, which will be practically every game in bot lane. Without them you'll take a great deal of extra damage from your opponent and won't be able to trade effectively.||||||
The choices are mostly quite straightforward here as far as Offence is concerned. You're an AD carry and your job is to do as much damage as possible, so you want to go deep into the tree picking up all the AD-based masteries while ignoring the AP ones.
|||||I take points in
and Feast instead of
because the Weaving masteries aren't particularly useful for Caitlyn as she is an autoattacker and the Feast sustain is incredibly valuable. I skip out one point in
because Warlord provides very minor bonuses and triggering Dangerous Game can be really game-changing in fights.
I like to spend the remaining 9 points in the Defence tree to pick up useful laning masteries. Block and Unyielding allow you to trade more effectively, more health is always extremely useful and 2 health regen is surprisingly significant early on.
|||||Heal is a great general defensive spell to improve your survivability in duels and teamfights. Use it in any situation where you need the extra health and movespeed to survive, or to bait enemies into suiciding for you. You can even use it to save your allies if you're feeling generous. Heal outclasses Barrier in almost every way due to being multi-target, providing movespeed and being permanent health instead of temporary. Just try to avoid healing during an Ignite if possible.||||||
Since your W and E skills are mostly for utility you should prioritize points in Q first for damage and poke. I prefer to level E next, because it gives you more escapability and more damage + a faster cooldown on your burst combo. Skilling W can let you spam your traps more effectively but it's generally not as good.
As always level R whenever you're given the option.
|||||Every 8 / 7 / 6 attacks (attacks while in brush count as 2, attacks against structures do not count), Caitlyn will fire a headshot, dealing either 150% damage to a champion or 250% damage to a minion.||||||//|
Make sure to try to use the shot on your lane opponents instead of minions whenever possible, because it'll hurt them quite a lot more than a normal attack. At the very least you can use it to zone your opponents back from last hits if they don't want to take the damage. It's worth noting that this charges twice as fast when you shoot from brush, so if you're fighting around brush your damage potential is amplified.
|||||Caitlyn revs up her rifle for 1 second to unleash a penetrating shot which deals 20 / 60 / 100 / 140 / 180 (+1.3 per attack damage) physical damage to targets in a line. It deals 10% less damage to subsequent targets, down to a minimum of 50%.||||||Q|
Caitlyn's main ability. This thing does high damage and has very long range, so use it to keep up the pressure on your opponent early game and chunk down their health. Once you get good at predicting your opponent's movements you can deal a lot of harassment damage through proper use of this ability. This is also your main tool for pushing the lane, as it will take a huge chunk of health from an entire_.minion wave.
Bear in mind however the 1 second cast time not only requires you to predict your target but also makes you vulnerable as you're forced to stand still for this time. Early in the game if you're fighting you should be sure to weave Q in after an autoattack whilst you're unable to attack to maximize your damage output. Later in the game once you have items ( ) finished you'll notice that because of the cast time you actually start to deal more damage with autoattacks than by using Q, so at that point in the game it's advisable to only use this to poke, when several enemies are clustered together, or when you're unable to reach your target with your autoattacks.
|||||Caitlyn sets up to three traps which trigger on champions. When sprung, the trap immobilizes the champion, deals 80 / 130 / 180 / 230 / 280 (+60% of ability power) magic damage over 1.5 seconds and reveals the target for 9 seconds. Traps last 4 minutes. When she sets a trap once the cap has been reached, the oldest trap will deactivate itself.||||||W|
This ability is one of the keys to what makes Caitlyn such a strong zoning champion. You can use these to deny brush control to your opponents, or put them in a line of three across your lane behind the enemy minions and make it very hard for your opponents to approach the minions or make any kind of play without receiving a lot of damage in return.
|You should be sure to place traps in chokepoints around the area when your team is attempting an important objective such as Dragon or Baron. If the enemy team show up they'll have a tough time navigating around them during the fight. If an enemy gets stunned by an ally, you can place a trap right on top of them to chain your CC. Also use these to block off the path of enemies who are chasing you or your allies.|||||
It's very important to keep in mind that these traps give a very brief period of vision when you place them down. This means that you can and should use these to check for enemies in unsafe brush or over walls.
|||||Caitlyn fires a heavy net to slow down her target by 50% for 1 / 1.25 / 1.5 / 1.75 / 2 seconds and deal 80 / 130 / 180 / 230 / 280 (+80% of ability power) magic damage. The recoil knocks Caitlyn back.||||||E|
Despite the misleading description the most important part of this skill is actually the recoil. This skill is Caitlyn's escape and it works basically the same as Flash, although unlike Flash it does have a short cast time during which you are still vulnerable - be careful with champions like Blitzcrank or Thresh who can easily interrupt it and leave you in big trouble. Use it to escape and cross walls by aiming in the opposite direction to where you want to go, and more rarely to chase down a low health enemy for the kill. Remember if you are being chased hitting the net will apply a significant slow on one enemy.
|||||Caitlyn takes time to line up the perfect shot, dealing 250 / 475 / 700 (+2.0 per bonus attack damage) physical damage to a single target at a huge range. Enemy champions can intercept the bullet for their ally. It provides vision of the target for the duration.||||||R|
Usually you'll be using this to pick off low health enemies who would be able to escape otherwise. Bear in mind that even though this can be blocked, the travel time is very fast so it requires close proximity or the use of Flash to block the bullet. You can get some unexpected kills in lane by hitting a good Q to take an enemy low and following it up immediately with this. If you can get both enemies low you're more or less guaranteed to get a kill on one of them. It can also be used simply to pressure an enemy into going back to base or stop a recall.
Do not use this ability in the middle of a teamfight. The massive cast time actually means that you'll deal much less damage than with autoattacks and you're a sitting duck while it channels. If your team is pressuring the enemy or preparing for a teamfight you can use it for poke on a squishy target without sustain (i.e. the enemy mid laner) assuming it won't get blocked by a tank. This is especially effective against a champion like LeBlanc who may often be away from their team looking for a pick.
Caitlyn's E skill has a few interesting interactions with her other skills, most notably the fact that it can completely cancel the animation for Piltover Peacemaker whilst launching it from where you were standing before you used E. This is done by quickly using E and pressing Q immediately afterward before you move (it might help if you're using smartcast).
The result is that your opponent has to deal with a hard to see Q coming from an unexpected place, possibly while also being slowed and damaged by your net.
This is a useful combo because it allows you to gain distance whilst dealing damage at the same time and can take opponents by surprise. You can also follow up by using your ultimate for a surprising amount of burst damage if your opponent is on low health. It also happens to look really cool. The video below is the best example I was able to find, but you should be able to figure it out on your own with a little practice.
Late Game Items
|||||This item gives you the best possible combination of stats for early laning. You have AD for last hitting and poke, health in case there's a fight or you're bursted and you have lifesteal to sustain every time you attack. If you're forced back with a low amount of gold and/or you're having trouble with sustain you should pick up a second Doran's Blade.|
|||||You have a little extra gold left over from Doran's, so pick up a health potion for some more lane sustain. Use it when you've lost a good portion of health from a trade to heal yourself back up or during an engagement to give yourself an advantage. Throughout the early game you should be sure to pick up 2 or 3 health potions every time you're in base and have gold left over.|
|||||This is fairly obviously the best of the three trinkets to start the game with. You get a short duration ward which is pretty useful for helping your support out with warding the lane brushes. Later, swap this out for Scrying Orb for long range scouting and potentially for setting up your ultimate.|
|||||This item gives you the highest amount of DPS of anything in the game due to the powerful crit passive and its' synergy with Phantom Dancer. Once you have this you have a cheesy 20% chance to do a huge amount of damage to your opponent, so you should try to poke with autoattacks and pray that RNGesus is on your side. Prioritize building either the BF sword or the Pickaxe over the Cloak of Agility because crit chance is worse than AD until you already have ~180 AD.|
|||||Boots are a requirement for every champion and these boots give the best stat for an AD carry, however the stats they give really aren't very helpful in most laning situations. If possible you should always focus on building up Infinity Edge before getting boots, though gold amounts don't always work out that way. If you happen to be at base with ~300-400 gold you can pick up Boots of Speed earlier in the game.|
|||||AS and Crit chance are must-have stats on an AD carry, combining with IE to give you a huge amount of autoattack DPS. Once you have this you'll hit a huge powerspike as you'll be attacking very fast and triggering IE crits 55% of the time, so you should be looking to teamfight. Compared to Shiv, PD gives you a later/slower powerspike and no useful passive, but does give you considerably more stats than Shiv. Since Caitlyn has no problems waveclearing and doesn't deal burst damage it's often better to go for the stronger sustained damage of PD.|
|||||This is an incredibly powerful item at this stage of the game, providing you with not only a big chunk of damage but also a huge amount of lifesteal that can allow you to heal up rapidly from the outskirts of a teamfight or from minions if you get poked or chunked while confronting the other team. The shield passive is also very useful because of how long it lasts; provided you attack minions every now and then it's essentially a permanent extra (up to) 350 health. This will protect you from 1-2 abilities, blocking poke and giving you a greater possibility to survive if you get jumped on by an assassin. If the enemy team is stacking armour, however, you may have to delay this item in favour of Last Whisper.|
|||||This could be the number one item that gets misunderstood by newer players and guide writers. Even if the enemy team is fairly low on tanks and only has one or two armour items this is still a requirement to buy on an AD carry and will give you more damage at this point of the game than anything else. Bear in mind that champions building armour are the most likely to be attacking you and moving into your range during teamfights. Once you have this, you are officially at late game god mode and you should be able to obliterate every enemy during fights provided you are able to stay alive and attacking.|
|||||It's pretty rare that you'll reach this point in a game but if you do you'll probably be wanting a defensive item to stop you from exploding instantly. There's a variety of defensive choices which excel in different situations, but BV is generally the best choice because of the high amount of stats it provides plus the insanely strong spellshield. It really screws with your enemies' ability to poke, initiate/catch and to burst you down. Even against a team with only one magic damage source the shield and health alone will help you a great deal. Alternative items: Blade of the Ruined King, Mercurial Scimitar, Guardian Angel.|
|||||Free AD and healing when you've finished all your items. Why not?|
|||||You can put this on your boots later in the game once your core is complete if you have some spare money to burn. It helps out somewhat with your kiting but it's not all that noticeable - there are more important things to buy.
Alternative items: Enchantment: Distortion, Enchantment: Homeguard.
|||||Can replace: Phantom Dancer. This is the better mid game oriented choice for your AS + Crit item, being cheaper than Phantom Dancer with a better build path and giving you strong up-front damage and waveclear using the lightning proc. A very strong strategy can be buying an early Avarice Blade (after Pickaxe or B.F. Sword), giving it extra time to stack up. You'll earn about 400 gold from it, making Shiv effectively about 700 gold cheaper than PD.|
|||||Can replace: Banshee's Veil. If you feel absolutely confident that you're not in any danger of being killed during teamfights you might wish to go for a full damage build by finishing with this item. You'll get crazy amounts of lifesteal and chew up tanks, plus a useful active for self-peel.|
|||||Can replace: Banshee's Veil. This is a great defensive item which also gives you a lot of extra damage. It works essentially the same as Cleanse, except notably it also works on several non-cleanseable ultimates - Warwick, Malzahar, Skarner, Mordekaiser and Zed are some examples that can be removed with the active. The weakness of this item is that it has less effect against a bruiser or assassin jumping on your face and won't stop you dying very quickly to damage. Remembering to actually use it quickly can also be an issue.|
|||||Can replace: Banshee's Veil. When you do a huge amount of damage, being able to come back for a round 2 can be pretty strong. This item is especially strong against fed assassins and burst champions who must run into your team and use their cooldowns to kill you, because they will waste all their abilities only for you to revive. The passive can easily go to waste, however, if you misposition and/or your team isn't able to protect your revive location.|
|||||Can replace: Berserker's Greaves only in ultra late game with all items finished. Selling boots for this item causes you to gain more damage, CDR and Tenacity at the expense of your movement speed, which makes it quite a risky thing to do. I don't generally recommend doing this unless you're extremely confident in you and your team's positioning because it makes chasing and kiting much harder, which can result in you actually losing DPS even though you have more damage stats.|
|||||Can replace: Enchantment: Furor. This enchantment is useful if you're in a situation where you are being forced to use Flash in every single engagement due to being heavily targeted by assassins or burst.|
|||||Can replace: Enchantment: Furor. This enchantment is useful in a situation where you're really behind in a game and find yourself stuck in your base a lot. The massive movespeed boost lets you get to lanes much faster, catch enemies and make plays when your base is under attack.|
||||||||||Janna is pretty crazy, especially with Caitlyn. With an Eye of the Storm on you, your trading is godlike as you won't take damage and have greatly increased AD for your autoattacks and Q. Adding to this, her ability to disengage and peel is unparalleled, making her the ultimate protective support. The only downside is that Janna herself is very lacking in damage.|
||||||||||Nami provides everything you could ask for in a support with her multiple CCs, buffs and heals. Her Tidecaller's Blessing works very well with Caitlyn because of her high range, making her autoattacks very dangerous and Nami's own trading damage is quite high. Nami can be hard to play however - she is incredibly squishy and missing her Aqua Prison can be fatal if you're getting engaged on.|
||||||||||Annie is extremely strong at initiating and winning fights, having the highest burst damage AoE of any support. Later in the game, her Flash + ultimate combo can devastate the entire enemy team. Her synergy with Caitlyn isn't great at first glance, since Caitlyn isn't great at following up on fights, but Annie does so much damage on her own that she barely even needs any help.|
||||||||||Lulu has some strong poke ability to compliment Caitlyn's, with her slow also making it easy for you to follow up with Q and autos. In addition she is great at keeping you safe with CC, shields, movespeed, and extra health from Wild Growth.|
||||||||||Braum's laning is unreliable because he has problems dealing with pushing and poking champions, but Caitlyn can mitigate these weaknesses and easily trigger his passive with her long range. Braum's teamfighting and late game is incredibly good, as he can lock down the entire enemy team for huge periods of time and is extremely tanky.|
||||||||||Morgana is another versatile support offering good opportunities for both poking and initiating fights with her Dark Binding, though missing it can be quite costly. Her Black Shield can also protect you from a whole bunch of nasty CC effects that would normally result in your death, as long as she's able to use it in time.|
||||||||||Thresh is a strong aggressive support with great gank assist, good defensive peel and the ability to pull you to safety when you're in trouble. Combine this with being tanky and Thresh is always a good choice. He can be quite a difficult champion to play however, and will have a bad time in lane if he's not able to pressure with his hook.|
||||||||||Vel'Koz brings a huge amount of poke in his kit to make this one of the most annoying lanes in the game, as well as having some of the highest base damages of any support - it's not too uncommon to see a late game support Vel'Koz top the damage dealt to champions graph. He doesn't have much in the way of actual supportive abilities though, and he's also very squishy if he gets caught.|
||||||||||Leona doesn't really synergize too well with Caitlyn, but she is still a great support. She has a huge amount of lockdown CC combined with being almost impossible to kill with her armour/MR shield and good early burst damage. Unfortunately even though traps can be used to chain CC, Caitlyn is still not the best at following up on Leona's initiations as she lacks damage.|
||||||||||Sona has a lot of laning power with great poke and decent healing and later in the game she brings a powerful initiating tool in her instant AoE ultimate. She's extremely squishy however and can die very easily if she gets caught by any CC.|
|||||||Zyra excels at pushing and poking, just like Caitlyn, as well as bringing AoE for teamfights. Her damage is very high in both laning and late game. Her weakness is that she's very squishy and immobile, dying instantly if caught out.|
||||||||||Karma, like Vel'Koz, has a huge amount of poke damage but not so much in the way of peel. Unfortunately Karma's damage tends to scale poorly throughout the game and after laning phase she's mostly only useful for the Talisman of Ascension-style effect on her Defiance to give your team mobility.|
||||||||||This lane can be very annoying since it allows Caitlyn to harass with neverending sustain. Unfortunately the problem with Soraka is that she's relatively useless in a fight and has no mobility with little CC, which means you are both at high risk of dying if you get caught by any abilities.|
||||||||||Blitzcrank is a kill focused support who likes to start fights a lot. Although he's pretty good at it, Caitlyn isn't really very good in a direct fight so I don't feel like this is a great combo. On the plus side he is very good at zoning with brush control.|
||||||||||At one time Taric was considered the #1 support with caityln Caitlyn, but after numerous nerfs his glory days are over. He still provides pretty good zoning and fighting ability in lane but his late game sucks and other supports can serve your needs better.|
||||||||||Nunu used to be absolutely ridiculous with Caitlyn but he has been nerfed a great deal since then. His W provides her with the steroid ability that she sorely lacks, giving her a large boost to her mid and late game, but in my opinion it's not enough to make up for what he lacks in other areas.|
||||||||||Alistar is quite a strong late game support as he's very good at protecting you from threats, however his laning phase is very bad in most matchups. His short range makes him an easy target for harass and his damage in a fight isn't high enough to make up for it.|
If your team has a jungler, you'll generally want to begin the game by protecting your team's jungle. For blue team a good spot to stand is the tri-bush next to bottom lane (this can be a dangerous spot if the enemy team has a Blitzcrank). For purple team you can stand just past the opening to your jungle near the dragon pit.
If you're on blue team and your jungler is starting with the Krugs or you're on purple team and your jungler is starting with the Gromp you can and should help them out a lot by assisting them with damaging the monsters - just be careful to leave before it dies so you don't risk taking the kill or the exp. Around three autoattacks is generally enough.
If your jungler is not starting on the bottom side of the map then a fairly advanced tactic is for you and your support to take the Krugs/Gromp yourselves before heading to lane. This involves trading aggro with you tanking around 3 or 4 hits and letting your support tank the rest (using a health pot). Some lane combos can do this much faster or more efficiently than others but generally you'll miss 1-2 lane minions and get level 2 more quickly than usual. I don't recommend trying this unless you trust your support, because it can backfire.
|||||Assuming you helped your jungler, when you arrive in lane you should find the minions already fighting but none should have died yet. It's very important in bot lane to make sure that you push the lane by damaging minions slightly harder than your opponent does at level 1 to ensure that you gain more experience and reach level 2 first. This gives you a window of opportunity to play aggressively and zone out your opponents since you and your support will have two abilities and better stats. If you're unable to do this and your opponents reach level 2 first you must play cautiously until you can equalize the level disadvantage.|
In general, the best strategy for farming minions is to allow them to fight until one is near death, and then pick them off with a single autoattack. This reduces how much your lane pushes, making it harder for enemies to gank and easier for allies. It also enables you to zone your opponent away from the minion waves much more easily if you get an advantage. However, another more aggressive strategy that works well with Caitlyn is to push continually up to the enemy tower by hitting minions with autoattacks or Qs - this makes it hard for your opponent to get last hits, allows you to harass them easily while they attempt to do so and puts pressure on the enemy team to respond to your push.
|||||Whenever there are no minions that are on low health, you can and should be taking shots at your opponents instead. Caitlyn's range is the highest in the game and you should abuse it as much as you can for free damage. If you notice that your opponent is about to try to last hit a minion, hit him with an autoattack or two and consider following up with a Peacemaker. In general you should try to establish your dominance and make them afraid to even come close to the minions. Be careful not to do this too much right away, since enemy minions hurt a lot at early levels.|
Caitlyn generally isn't the best in all-ins unless her opponents are already poked to low health, but you should always be ready to back up your support. If there is a fight at any point, make sure to kite by moving around in between shots. If you don't issue a move order Caitlyn will simply stand there doing nothing in between autoattacks, which is wasteful and can be dangerous or cost you kills. Always hit the biggest threat to you, which is most likely going to be the AD carry. If you're able to get kills on your opponents you generally want to push the minions up to the enemy tower by autoattacking and Qing as fast as you can and return to base to buy items. Pushing the minions in this way means that your minion waves will hit the enemy tower and die on it before anyone can arrive, giving no experience or gold to the enemy team.
|Hopefully you're winning the lane. If you feel like you're ahead, you can attempt to place traps across the lane and stand on the minions or even between the minions and your opponents. This forces them to navigate your traps and take free damage every time they attempt to get close to the farm. Regardless of whether you're ahead or behind, it's always a good idea to place a trap into brush your enemy controls to deny it to them. If someone walks into a trap, you have a free hit with Peacemaker and perhaps several autoattacks. If you're significantly ahead or some members of the enemy team are dead and your Jungler is nearby, you should attempt Dragon so you can get some nice buffs and begin stacking it up.|||||
If you should fall behind and no longer feel safe to zone and harass, just try to pick up as many last hits as you can without getting into danger and hope your team assists you. As long as you're careful to keep up your cs you can still get yourself back into the game later on. One last thing to remember is to check items. Items like Vampiric Scepter and B. F. Sword make a great deal of difference to the lane and knowing which areas you're stronger and weaker in compared to your opposite is important.
This is probably the most vague section of the game and the part that newer players might struggle to understand the most. Mid game generally begins as soon as outer towers start to be destroyed around the map, allowing players to begin roaming to other lanes and moving around in groups to make things happen. It's not uncommon at this stage of the game for a team to attempt Dragon or begin ganking and pushing lanes with 4 or even 5 people which makes it somewhat unsafe for you to continue laning in the river area, especially if your tower is already dead.
This is also the stage in the game where Caitlyn is usually weakest. Skirmishes begin to happen more regularly here and as I mentioned Caitlyn is quite weak in direct fights. Without items your autoattacks don't deal very much damage and your skills are not very effective at DPS. You have a few options here depending on how well you're doing.
You can always:
- Try to destroy the enemy bot lane tower if it's not already dead (might require your team to help if you're behind).
- Roam and try to get an advantage by picking up Dragons, kills and the mid lane tower. Bear in mind the enemy bot lane can farm freely while you're gone.
- Take a jungle camp. Try not to steal camps that your jungler is heading towards though, since they gain extra gold.
If you're ahead you can:
- Stay in bot lane and keep zoning and freezing the lane. Bear in mind the enemy bot lane may roam, so be prepared to push out quickly so you can help your team.
- Stay in bot lane and push like crazy with your support. This will put pressure on the enemy team and force more players to come to bot lane to deal with you.
If you're behind you can:
- Freeze the lane by tanking minions before they hit your second tower and only last hitting them. Done properly, this causes the minion waves to stay on your side of the map for a very long time and is by far the best way to catch up when you're behind in cs - however, your opponents are free to roam to Dragon and mid lane and your team may have difficulty without you. If you're really far behind then you probably won't be able to help them much anyway.
Even if there's a lot of action around the map, try to keep an eye on your own lane and return periodically to farm up the gathered minion waves. Keeping up in farm whilst controlling objectives and assisting your team is difficult but very important to the role of AD carry.
Late game is the point at which it becomes extremely unsafe to be moving around without your team and getting caught or losing a teamfight will result in immediately losing Baron, Inhibitors or even the entire game due to long death timers. Generally at this stage of the game AD carries will have completed most of their core items (in this case IE + PD + BT) and will be doing a great deal of damage. You should still return to lanes to farm large gathered minion waves, but don't stay in a lane alone for any longer than necessary or you could find yourself getting caught or the enemy team rushing a Baron. Stick with your team as much as possible.
The most important skill to work on when playing an AD carry is positioning and kiting. This means ensuring that you are never in a position where the enemy team can stun and immediately kill you. Generally you want to stay as far back as possible - ideally, at maximum autoattack range from your target - and target the enemies that are most threatening to you. It's likely that at least one of the enemy team's tanks/bruisers/assassins will try to get to you and either kill you or force you out of the fight. Don't panic and keep moving in between shots. Remember that you have E, heal and flash and be ready to use them when necessary to gain more time or distance.
You may encounter people who tell you to focus carries and ignore tanks but generally these people do not understand how to play AD carry. It's very rare that you'll get an opportunity to properly focus an enemy carry and when you do it's usually because they made a big mistake or got caught. Most of the time you'll be forced to target tanky champions before you can break through to the enemy back line - this is one of the main reasons why you buy Last Whisper. Only if the enemy tanks are very low on both damage and disruption is it occasionally possible to simply ignore them and proceed straight to the enemy backline.
Above all, staying alive is the most important objective. Without your damage your team will probably lose the fight, and you don't do any damage when you're dead. When in doubt, just attack the closest enemy.
Thanks for reading!
Special thanks go to MissMaw, who did almost all of the coding and pictures for the guide. c:
If you have comments, suggestions or questions please feel free to post here or send me a private message. I will read everything and reply to questions and criticism.