Try to knock enemies back into your towers with Explosive Cask.
Try to combo Body Slam with Explosive Cask to set up kills for your team.
The damage reduction from Drunken Rage is applied when you start drinking, try to use it when you see damage coming your way.
When Kayn is in terrain near you, you will get a visual warning on the edge of the terrain he's in.
Umbral Trespass requires Kayn to damage a target first. Try to dodge Blade's Reach to deny him a long range cast of Umbral Trespass.
Damage Kayn while he's in Shadow Step to shorten its duration, or apply hard crowd control (stun, charm, knockup, etc) to end Shadow Step immediately.
The stat comparisons provided here underscore several important Gragas versus Kayn counter stats that may help us explain the differences and similarities between this set of champions. For instance, Gragas’s KDA ratio ([kills + assists] / deaths) of NaN is better than Kayn’s ratio of NaN, showing that Gragas may be more central to his team's team fighting capacity than Kayn..
Gragas usually has a similar longest killing spree as his opponent does. On average, he takes less damage than Kayn. This typically indicates differing health capacities; however, it can also indicate that the champion with increased HP has less mobility and thus is unable to escape further damage when poked or engaged.
Both League of Legends champions are great champions. Both champs have their pros and cons. In the game's current meta, Gragas usually loses when facing off against Kayn, with a 48.3% win rate. Thus, Gragas makes a bad counter for Kayn.
While Gragas does have a lower win rate than Kayn, when on opposite teams, Gragas also has a lower learning curve that makes him a less complex champion to develop with. You still need to be cautious when picking Gragas into Kayn.
Additionally, Gragas has a good amount of CC and other utility, a similar amount to Kayn. This often makes her just as valuable during teamfights, especially when trying to counter champions with a ton of burst damage.
While there isn't a single best champion overall in League of Legends, in Gragas vs Kayn matchups, Kayn is the better champion with a lower win rate, less champion complexity, and a similar amount of utility to help out your allied champions during team fights.
Gragas is a somewhat poor counter for Kayn. You will do well by focussing your play on maximizing your gold and cs and taking out objectives. If you do that, you should hold your own as Gragas against Kayn.
To learn all of the intricacies of Gragas to counter Kayn during both the lane and mid / late game phases of League of Legends, you should keep reading to learn a few extra lessons on this matchup. If you mind the build and suggestions displayed above, you should grow your win rate significantly and be that much closer to League of Legends pro players.
Gragas on average racks up more CS compared to Kayn. Champs who typically don't take many minion kills typically don't need much CS to be valuable teammates, such as support champions. These kinds of champions are capable of scaling well off of their skills, stats, and first items alone. Yet, champions with a lot of CS, such as hyper-carries, often require several high cost items to be effective. In either situation, try to do better than the values displayed on this page to do well.
The ideal items to have in your Gragas versus Kayn build consist of Void Staff, Shadowflame, and Stormsurge. When Gragas bought at least these three items in his build, he did much better versus Kayn than with most other commonly used counter builds. In fact, Gragas had an average win rate of 48.3% when playing against Kayn with these items in his kit.
To have the best likelihood of crushing Kayn as Gragas, Gragas players should use the Phase Rush, Manaflow Band, Transcendence, Scorch, Biscuit Delivery, and Cosmic Insight runes from the Sorcery and Inspiration rune sets. Of all the rune combinations players picked for Gragas vs Kayn matchups, this composite of runes resulted in the highest win rate. Notably, these runes averaged a 48.3% win rate overall.
If you want to view Gragas x Kayn tips and matchup stats and build suggestions for a a particular rank, feel free to choose one from the selection menu shown above. By default, the stats and guides given are calculated using every match run with both champions.