How can I counter Ahri in lane?

I dont really know what to look after when I lane against Ahri making the game harder to win. Which champions are a good counter for her and why?

Ahri is a strong pick really. You can either pick something really deffensive and just farm (if that suits your placestyle) like Galio or Karthus, or you pick something that builds tanky (since ahri has no real sustained dmg), like you said Morde, Ryze, Galio.

I know from experience that Kennen and Vlad win against Ahri, cause Ahri is really weak on the first few lvls (1-3) and Vlad can outsustain her (even after these first lvls) while Kennen can outdmg her (due to his superior autoattacks), so try these out.

Or if you really have problems against Ahri, you can try TF. He is somewhat risky, since she can easily burst you if she gets ahead, but the good thing about tf is: you can just push till lvl 6, gank sidelanes, go back to mid and push on long range with your Qs.

Edit: against a good ahri, morde will loose without the right runes. Ahri will just use AD runes and autoshot you down on lvl 1 or 2, and after the first lvls, she will ask her jungler for ganks, and there is no way a morde can escape from an ahri charm + jungler presence. So only pick Morde if the enemy has a weak early jungler!!

Ahri is a really solid pick right now due to her mobility and the short cooldown on her Charm (E) ability. This makes her a very good ganker and helps her control side lanes. All the while she is still a strong laning champion as well.

There are a few ways to nullify or even abuse Ahri's mobility though. To counter her here, you'll need to pick a champion that has high burst and a reliable stun (Meaning not Viktor or Brand) on a shortish cooldown, or a good assassin such as Talon or Kassadin. I'm sure this doesn't need to be said, but you should obviously be warding your lane to protect yourself from getting ganked by the enemy jungler. Ahri's Charm(E) + Jungler CC = Dead You, regardless of the character you're playing.

Probably the strongest pick against Ahri is still AP Sion because Ahri can't burst down his Death's Caress(E) and he'll push lane all day while denying Ahri with his Cryptic Gaze(Q).

Other Strong Picks Include:

Morgana: Just harass Ahri with Morgana's Dark Binding(Q) into Tormented Soil(W), and just Black Shield(E) Ahri's Charm(E). Morgana will have a much stronger presence in team fights due to her significantly stronger ultimate, Soul Shackles(R).

Annie: Harass Ahri early every single time a stun is up. Pop her with Disintegrate(Q) into Incinerate(W) for a pretty huge poke whenever she tries to go in for a CS. After level 6 Annie will have significantly higher burst and a much better teamfight presence due to Tibbers(R) bombing people in the face. Just remember to laugh manically every time you land a successful Tibber Bomb. It is as instrumental to playing Annie as yelling "Worth It!" in all chat is to playing League.

Veigar: Veigar's Event Horizon(E) will make Ahri's mobility meaningless. Just land Event Horizon on her, and land his Dark Matter(W) + Baleful Strike(Q) combo while she is stunned for heavy poke. After level 6 hitting Ahri with Veigar's Event Horizon(E) should pretty much land a kill 90% of the time. Just use Dark Matter(W) + Baleful Strike(Q) + the appropriately named Primordial Burst(R) to damn near instantly drop Ahri (or any AP carry for that matter). Veigar also scales into late game much stronger than Ahri does due to Baleful Strike's(Q) passive permanently increases Veigar's AP when it kills a minion or when Veigar kills a champion with any ability.

Kassadin: Pre-6 Kassadin will either have a difficult time, or just mostly farm. Ahri's Orb of Deception(Q) out ranges Kassadin's Null Sphere(Q) so you can't really get silences out on her before she goes in to harass you. Post-6 though Ahri will struggle, as Kassadin is much more mobile and can silence with Null Sphere(Q) for a strong amount of damage. Using Riftwalk(R) to get in and then using Null Sphere(Q) to silence and keep Ahri from retaliating and then using Kassadin's Force Pulse(E) before using Riftwalk(R) to get back out again. You take little to no damage and just did a huge amount of burst. Kassadin is designed to destroy a vast majority of AP Carries in this way.

LeBlanc: Similarly to Kassadin, LeBlanc is an assassin burster who has high mobility and a silence. The major difference here is that LeBlanc can start her harass combo much earlier than Kassadin, and won't have the same pre-6 issues that he does. Landing LeBlanc's Sigil of Silence(Q) into her Distortion(W) causes some quick damage and just reactivating Distortion(W) will return LeBlanc to her original location. No damage taken, tons of damage dealt. Once LeBlanc gets her ultimate Mimic(R) you can easily toss that into her combo after Sigil of Silence(Q) for even more damage. If you know Ahri's ult is down you could land LeBlanc's Ethereal Chain's(E) to root her and chain even more spells together.

Talon: Talon is also fairly similar to LeBlanc and Kassadin. He is also a mobile assassin with an on command silence (go figure!). The main difference here is that Talon is an AD character not an AP character. Using Talon's Cutthroat(E) to get in on Ahri and then it is just a matter spamming the rest of Talon's abilities and punching Ahri in the face. Talon's Rake(W) is decent ranged harass early on, but similar to Kassadin's Null Sphere(Q) Ahri's Orb of Deception(Q) outranges Talon's Rake(W).

Those are all the champions I can think of that counter Ahri in lane. League of Stats suggests that Karthus can do it, but I just don't really see it. I guess he scales better and has a vastly superior teamfight presence, but I can't see him winning the laning phase. I could be wrong on this one though. Perhaps Karthus's ability to spam his Lay Waste(Q) and the fact that it has higher range than Ahri's Orb of Deception(Q)? I'll look into that one a bit more. Additionally, Malzhar may also be a counter, but I haven't played him enough lately to feel confident saying he is. He probably will be for sure after the Zyra patch though.

A few notes:

• I picked champions that would counter Ahri and win the lane, not champions that would just lock the lane or tie with Ahri. Because of this you'll have to note that Ryze and Twisted Fate aren't listed as counters. Ryze has to get up in Ahri's face in order to do his full potential, and while he does lock Ahri out of using her ultimate for a few seconds he is still vulnerable to Ahri's full potential because she has to get up in someone's face to do it too. This, on top of the facts that Ahri's harass out ranges Ryze harass and Ahri's lane pushing abilities are far superior means that the match-up is very even if not slightly siding with Ahri. Twisted Fate just pushes the lane and goes to gank, essentially making the match-up even through lack of aggression in mid. Twisted Fate will just go elsewhere for his kills.
• I can't really explain good enough how important it is to anticipate her skill shots and dodge them. Surviving a gank or getting destroyed can easily be decided in your ability to dodge Ahri's Charm(E).
• If you're getting crushed against any mid champion as any mid champion grabbing some magic resist is always a good idea. No one is going to yell at you for getting Abyssal Scepter and Banshee's Veil.
• Letting your jungler counter Ahri for you is also not a bad idea. Especially if you want to take a specific champion for team comp reasons. Warwick counters Ahri easily, and so does Shen and Shaco.

Sources:

• League of Stats
• Elementz's Ahri Guide on LolPro

Ryze is a good counter, he shuts down her mobility and gets pretty tanky to out-sustain her.

Also Talon does well, he can silence and burst her down.

In general, any champ that has a silence and/or some form of lock down CC do well against an Ahri.

I am surprised that most people don't consider Mord a hard counter to Ahri. I am sitting in between 1550-1650 elo and I play a lot of Mord. What I usually do is focus on harassing her while getting minion kills simultaneously. Mords sheild does a lot of work against he slow spell sequence and by level 8 or 9 when I have a pretty solid item build including spell vamp I have absolutely no problem killing her. Ahri also has a pretty slow attack animation and her range is low. So you have plenty of time to hit her with mord spells while she goes in for last hits. Hope this helps.

You want a counter to Ahri? Take Swain. He's got everything you could want against her:

• His damage is a dot, so even if she escapes, she's still taking damage.
• He has a root, helping, allowing him to do damage or a jungler to close in for a gank
• He can clear waves too, so pushing him into his tower doesn't ruin his day like it would a LeBlanc
• He has even better sustain than Ahri, so she can't poke him down into kill range
• He WANTS to be in close, so if Ahri jumps in on him, he's actually at an advantage, neutering her ultimate.