AD Carry Basics:
1. GET LAST HITS. While getting kills is all good and well, assuming that there are no major mismatches in lane getting kills without jungler help is easier said than done.
Focus on getting last hits and harass if a window of opportunity opens.
2. Unless your support is a complete derp, BACK HIM UP. If your support goes in for harass and the other team tries to jump on him, GO IN AND DPS THE OTHER TEAMS AD. I constantly see bad AD players turn and run off the second something bad happens to their support (Taric stun, blitz grab, leona initiate). Sometimes this may be neccessary, but if its a 2 on 2 situation and you are relatively healthy you should be backing your support up by dpsing the other teams AD carry. This can force them to back off which reduces the damage your support is taking, and you can then turn on the opposing support player if nothing else is in range.
If your support is doing his job (Eating damage and CC for you) but you are constantly running away and leaving him out to dry, this undermines any confidence he may have in you and can lead to you losing lane (He won't stick his neck out for you if you don't do the same).
If you feel that he shouldn't be playing aggressively, TELL YOUR SUPPORT so he knows that he should stop harassing or zoning. Don't say absolutely nothing then yell at him 1 minute later when the other teams mid and jungler show up.
3. Don't die or take stupid risks. Sometimes a kill window may open, but it might be extremely risky (You and your support may have to go balls deep, you have no wards in river and have no idea where the opposing teams jungler is, the other team may have shen/TF, this list goes on). If it looks risky and might end up with both you and your support dead, don't do it.
4. MAP AWARENESS. Keep an eye on the map. If you see the opposing teams jungler trying to gank top, this is a good time for you and your support to be more aggressive. On the flip side, if you see your own teams jungler coming in to try and gank for your lane, try to bait the other team into doing something aggressive.
5. If you have a jump/blink, think very hard before using it offensively. I think we've all seen Ezreal/Tristana/Graves/Corki players who thought they were hot **** jumping into the middle of a fight only to get killed 3 seconds later due to focus fire.
6. DON'T DIE. In the late game, if you get picked off stupidly that can single handedly lose the game for your team. The AD carry is quite possible the most important member of the team when the late game rolls around, so act like it. Don't go around w/o your support in tow, and be very mindful of your positioning.
Some advanced AD carry tips:
1. Good times to harass:
-Enemy ADC is running up to get a last hit
It is easy to detect when the opposing ADC is going in for a last hit. When they do you, you can sometimes tag them with a skill as they are autoattacking.
-Enemy ADC tries to go in for a harass attempt but fails
You've all seen it. A Tristana goes in to try and tag someone with her E but doesn't make it in time. As she is running back to her usual safe last hit range, you can sometimes land a skill and/or auto attack.
-Your creep wave is bigger than their creep wave
If you have a cannon minion and a bunch of smaller minions and all they've got is 2 ranged minions, if positioning allows for it this is a good time to try and start a fight.
2. Good times to go in for a kill (You want at least 3 or more of the following to be true before you try to go in for a kill)
-Enemies are lower health than you are due to harass
-Enemies are pushed up in lane
-Enemy has no major CDs up(If you see the enemy teams Alistar fail his combo and waste his knockup CD, it may be a good time to go in).
-You have river well warded (If your support doesn't have good ward uptime on river, he may well be a moron. If this is the case help him out by buying a ward occasionally).
-The enemy jungler is nowhere near you
-The enemy mid is nowhere near you
-You have accounted for enemy global ults and/or teleport.
-You have told your support to be ready to go in
3. Control the minion wave
You can easily gauge where a minion wave is at any given time simply by looking at your own minion wave.
You see alot of people who say that you should never push and to keep your wave central at all times. While this is good for some situations, there will be times where pushing the creep wave up to the opposing teams tower can be extremely beneficial:
-You harassed like a champ and the other teams AD decided to go back to heal and buy. Shoving the lane up to the tower when he is away will cause him to lose CS and exp.
-You are stronger than they are and they are playing hyper passive. Shoving the lane right up to the tower can deny the enemy AD CS.
Just don't do it wrong. You want your wave of minions to reach the enemy tower when the enemy creep wave is nowhere near it.
Alot of people do it badly and shove the wave to the tower just as the enemy creep wave reaches the tower. This allows the enemy ADC to comfortably CS under the tower out of danger and this forces you and your support to be extremely over extended. If this happens you want to quickly auto attack the enemy minions and force a reset to the centre of the lane.
Stay behind your tanks in teamfights. If you are alone off to the side and not with your team, it is stupidly easy for a single bruiser to zone you away from a team fight or simply flat out catch and kill you. Meanwhile, the enemy AD is happily shooting away since his team can actually CC and peel for him.
5. Target Selection.
See all those idiots who say "Don't focus fire the tank omg!" and expect you to somehow walk through the enemy teams tank line to hit they enemy AD and AP carries?
Don't listen to them.
Of course, if you have a choice between shooting Zyra and shooting the Malphite with Randuins and Frozen Heart who is standing right next to her, you should shoot Zyra.
However, what is Zyra is standing next to her AD carry all the way behind malphite?
Unless the other teams tanks have downs syndrome, they are not going to let you stroll up to their squishies so that you can do mad deepz to them. They are going to CC you and beat the living **** out of you.
As an AD carry, as soon as it is safe to do so you want to sit down and get out as many auto attacks as possible out on something. Sometimes the other team will have a juicy target walk near you so you can kill them. In most cases though, you are going to end up shooting a bruiser or a tank.
1. If it is likely that you will die before being able to reach your target, choose another target.
3. Its okay to shoot tanks and bruisers if trying to reach anything else will get you killed.
3. When you have Infinity edge, Phantom Dancer and Last Whisper, almost everything is a viable target.
There is probably lots more you need to know to play AD well, but those things you will get through actually playing the game and getting experience. There is only so much you can get from a guide.
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