What if I told you...
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I know, I know, crazy concept, isn't it?
Lately, there has been alot of fuss regarding the "OP-ness" of assassins. In fact, one of the highest voted threads (at the time of writing this) is specifically aimed at this issue. The author of the thread goes on a rant about how he can be killed so easily by an assassin with an insane amount of damage, and then have that assassin escape with some sort of escape mechanic, coming out essentially unscathed. And that is generally what the entire community is complaining about; assassins are unkillable, killing machines!!! And if you don't pick or ban them, you basically lose the game.
However, there is one simple thing that all assassins benefit greatly off of. This one simple thing is why they dominate in solo queue, but are unable to make that much of an impact in team games (like LCS games). No matter how much you want to deny it, EVERY assassin benefits greatly off of this one simple thing. What is this, you ask?
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Mistakes. Whether it be bad positioning, bad timing, or bad choices, every assassin in the game benefits off of something we make every day. No one can deny this. In fact, some of the assassins are strictly known for capitalizing on mistakes (for example; Talon). So, how does one keep an assassin down despite the fact that eventually you will make a mistake? Well, you first have to know which specific mistakes each assassin uses, then know what their biggest weaknesses are. Lets go through the list, shall we?
Ahri
Despite being changed into more of a mage recently, Ahri still holds some really good assassination potential. Being one of the few champions that has a fail-safe, it is difficult to capitalize on her mistakes without her simply running away. The main mistake she tends to benefit the most off of is bad positioning. Anyone half way decent at Ahri can snipe an enemy carry with a charm in the middle of a teamfight, instantly turning the fight in her team's favor due to said carry getting turned to dust within a few short seconds. If you are even slightly out of place, Ahri will not hesitate in trying to lock you down, and then proceeding to chunk three quarters of your health with a single combo.
So, how do you stop Ahri? Being the mobile assasin like mage she is, crowd control is her worst enemy. If you keep her from moving long enough, whether it be with a snare, stun, displacement, etc., she can not, and will not survive much longer. The only hope she has at surviving an onslaught of damage after getting cc'ed is to land a charm on the biggest damage dealer, and hope for the best. But even then, she will need either her ultimate, or a flash in order to get out of those situations.
Tenacity, of all things, also really hurts Ahri. Charm is affected by Tenacity, and the less time you are under her charm, the less damage you will take. Its that simple.
Akali
Thankfully, Riot did realize that Akali was quite strong, and did proceed to give her appropiate nerfs, something she has needed for a very long time. However, Akali is still an assassin, and still benefits off of mistakes, and the specific mistakes she benefits greatly off of is actually bad decisions. Akali is one of the assassins that goes in, and stays in. Unless she has flash, an enemy minon, or jungle monster behind her, she has no means of escape. Thus, if you can't capitalize off of her commitment to getting a kill, then you somewhat deserve to get blown up.
Akali's biggest weakness is vision. Whether it be regular vision, or true vision, this is what the pros tell you all the time to take against her. Akali's only defensive ability is her shroud, where she sits in relative safety, waiting for her cooldowns to come back up. Take this away from her, and she is extremely vulnerable. After you have vision of her, you can proceed to lock her down with any form of crowd control, and blow her up.
But that's just true vision, using regular wards also inhibit's Akali's power. Most assassins do not get fed off of their opponent in lane, for it is usually bot lane that they get fed off of. If your bot lane has enough warning of her roaming towards the bot lane, then she will either have to back off, or commit to a tower dive, something that is not easy to do, regardless if you have back up or not.
Fizz
This poor little fish also got nerfed quite hard recently. The old Fizz could decimate an entire team with ease, and come out of a fight with barely a scratch. Riot realized this, and took away alot of his power from his normal abilities, and moved that power into his ultimate. Now that he is FAR more ult reliant, there is plenty of counterplay to him, such as just dodging his ult (which is, surprisingly, quite easy to do). The mistake that Fizz tends to benefit off of is bad timing. Yes, Fizz's troll pole is still a very reliable means of escape, but there are times where Fizz uses his Playful/Trickster to get close enough to his target in order to fully close the gap with Urchin Strike. If the proper crowd control is not put on him at the right time, he will destroy anyone he chooses.
Interestingly, Fizz's weakness is actually the opposite of his strength: good timing. A well timed Zhonya's, QSS, or some type of invulnerability can negate a TON of his damage. Also, any well timed crowd control to lock him down and keep him from closing the gaps will keep him from doing anything.
Kassadin
Ah, Kassadin. The hyper-mobile assassin that has seen his hayday. Unfortunately, he is due for another nerf, something that has become all to familiar to Kass players. But, he is still an assassin, and thus benefits off of some sort of mistake, that being bad decisions. Kassadin has an utterly awful early game and a mediocre mid game. If you can't keep Kass shut down for the first 25 minutes of the game, he will come back and annihilate you in the late game. Yes, he is very difficult to kill, and even with the incoming nerf, he will still be very difficult to kill; but as long as you can deny him farm and kills, it will only take him longer, and longer to reach that point of no return.
Like Fizz, Kassadin's weakness is good decision making. You can't really kill him unless he himself makes a mistake because of his extremely reliable mobility, but you can constantly harass him out of farming and teamfights. Your job against a Kassadin is to prolong that point of no return as long as possible. Can you keep it from happening completely? Unfortunately, no, that is impossible unless you win the game before that threshold.
Katarina
Due to all of the assassin changes, Katarina is quickly rising in the ranks of the top assassins, and Riot has noticed this. Although they have plans to deal with her rise in power, we have no word as of yet to what those plans are. Kat tends to benefit off of bad timing. Forget positioning with her, if she is allowed to do so, will steam roll your entire team within a few short seconds. However, she is somewhat similar to Fizz in that she is very reliant on her ultimate, the ability where she gets most of her damage from. If you don't have the tools to stop her ultimate, she will not hesitate in slicing right through you.
Kat's biggest weakness is actually crowd control, specifically stuns, silences, or displacement (snares cannot interrupt channels). Her ultimate is a channeled ability, so if you have some way to knock her out of it, USE IT. If you don't have any of that specific crowd control, she will very easily start raking in those kills.
LeBlanc
LeBlanc was actually one of the first assassins to get nerfed (behind Kass), losing a silence on her Q which kept her targets from fighting back. After a bit of a dull period, though, she has come back. Not nearly as dominant as before the nerf, but still in quite a healthy place. LeBlanc benefits off of bad positioning. Similar to Ahri, LB's goal is to go in, deal as much damage as possible within the shortest amount of time possible, and get out. If she sees an opening in which she can get to a carry, she will not hesitate to jump on it. If the carries cannot keep their distance from her, and let their front line deal with her onslaught, then they have no hope of winning the game.
LeBlanc's weakness is similar to Kass and Fizz in that its the opposite of her strength: good positioning. If the carries do not let her get close to them, then she becomes pretty useless, with nothing more then a snare to slow a target or two down. She is also hurt by any kind of invulnerability or high sustain. Since she is meant to get her combo off in less then a couple seconds, just blocking even one of her abilities can destroy her entire combo.
Talon
Talon has to be the most well known champ for capitalizing on bad positioning. However, this isn't positioning in a teamfight, this is your position on the map. If your a carry, farming a lane all by your lonesome, then there is a pretty high chance that Talon is on his way to kill you, or is right behind you, invisible, and just trying to get in range for his E. Even as a tank or fighter, if you are alone, you are at risk of getting blown up Talon. This doesn't necessarily apply in teamfights (although, it certainly can), because Talon has to commit to his target even more then Akali does. He doesn't have multiple dashes to potentially get away, and his only means of escape (his ultimate) is normally used as either to get to a target, or just throw in a little more damage to his target.
His weakness is the opposite of his strength: grouping. If he has to dive into the middle of a team to get to a carry, chances are, he won't have the time to blow them up before he himself gets locked down and blown up. You NEVER want to be alone when Talon is on the field, and laning phase has ended, because it is just stupid.
Zed
The one champion you all have been waiting for. Zed is one of those champions that the community is begging for nerfs on, because he is just that good. He has the greatest outplay potential, he deals a fricken TON of delayed damage, and he can get to carries in the middle of a teamfight. From first glance, it seems that Zed doesn't have to benefit off any mistake, because no matter how well you do, he will still kill you. Well, this isn't true. Zed actually benefits greatly off of bad decision making. There is a guy named Redmercy who is a somewhat popular YouTuber (at least amongst the League community), and he has to be the best Zed player in North America hands down. From watching his videos, I have learned alot about the assassins, and specifically Zed. All in all, Zed is actually very ultimate reliant, about as much as Fizz currently is. Also, management of Zed's shadow placement is what separates the good Zed players from the great Zed players, and this is where the bad decisions of his opponents come into play. Many people tend to ignore Zed's shadows, and the Zed player can take full advantage of this. If a carry is able to get away from Zed when he ult's them, but escapes in the direction of a shadow, Zed can easily teleport to that shadow, and finish the job.
Zed's weaknesses lies mostly in how the team reacts to him. Now, this is unique only to Zed, because there are numerous champions and items that can completely negate the damage from his ultimate. Zhonya's and QSS are really big items to build when playing against Zed, because they make him utterly useless. Shields, surprisingly, are also really good against Zed, since they soak up a decent portion of his initial damage when he ults. If he is ever to get locked up with crowd control right after his ult, and not be able to deal any additional damage, his ult will deal a very insignificant amount of damage. So little damage his ult will deal, in fact, that it will only tickle even the squishiest of carries.
There are many ways to outplapy Zed, and only the greatest of Zed players can outplay those outplays (Watch Redmercy's intro video on his YouTube channel. Its insane!). Predict his moves, and you can easily shut him down. Play predictably, and Zed will proceed to steam roll you.
Well, that's it for this thread. I will release another thread shortly explaining which champions are actually the best in going against assassins, a little sub-category that I like to call "anti-assassins".
I hope this thread sheds some light on this whole assassin situation, and at least shows the community how assassins work, and what they benefit of off.
TL;DR The less mistakes you make, the less powerful assassins are.