Roar of the Slayer is a great setup ability to land a very powerful Decimating Smash.
The Soul Furnace buff displays how much shield strength is remaining, use this information to time its explosion perfectly.
You only have very slight turning ability during Unstoppable Onslaught, so make sure to use it in straight paths.
Dodging Arctic Assault and Glacial Prison can give you a huge advantage.
Focus on avoiding the second swing of Winter's Wrath which carries the brunt of the damage.
Melee enemies can also stack Frost for Sejuani, be very careful around them.
The stat comparisons shown on this page clarify several influential Sion against Sejuani matchup statistics that may help you realize the differences between this pair of champions. For instance, Sion’s KDA ratio ([kills + assists] / deaths) of NaN is better than Sejuani’s ratio of NaN, highlighting that Sion may be more central to his team's team fighting capacity than Sejuani..
Sion often has a similar longest killing spree as his foe does. On average, he takes more damage than Sejuani. This typically indicates different amounts of tankyness, but it can also indicate that the champion with higher HP has less agility and thus is not able to kite away from additional damage when poked or engaged.
Both League of Legends champions are great champions. Both have their pros and cons. In the game's current meta, Sion usually wins when playing against Sejuani, with a 51.5% win rate. Thus, Sion makes a good counter for Sejuani.
While Sion does have a higher winrate compared to Sejuani, when on opposite teams, Sion also has a greater level of difficulty that makes him a more challenging character to learn. You should be careful when picking Sion into Sejuani.
Furthermore, Sion has a good amount of CC and other utility, a similar amount to Sejuani. This makes her just as valuable during team fights, especially when trying to counter champions with a ton of burst damage.
While there is not one best champion for every situation in League of Legends, in Sion vs Sejuani matchups, Sion is the better champion with a higher win rate, more champion depth, and a similar amount of utility to help out your team members during late stage team fights.
Sion is a decent counter for Sejuani. You will do well by focussing your play on increasing your CS and taking out objectives. If you are able to do that, you should be able to stand on your own as Sion against Sejuani.
If you would like to truly master Sion to counter Sejuani during both the early game and mid / late game phases of League of Legends, you should keep reading to pick up a few extra tips and tricks for this matchup. If you listen to the build and stats displayed here, you will increase your win rate significantly and be that much closer to League of Legends pro players.
Sion most often accumulates much more CS as Sejuani. Champs who typically don't acquire many minion kills typically don't require much CS to be valuable teammates, such as sup champs. They are able to scale properly off of their skills, stats, and first items alone. Yet, champs with a lot of CS, such as hyper-carries, often require several high cost items to be effective. In either situation, try to exceed the values reported on this page to do well.
The most important items to use in your Sion versus Sejuani build include Unending Despair, Sunfire Aegis, and Heartsteel. When Sion used at least these three items in his build, he performed much better versus Sejuani than with many other typical item sets. In fact, Sion had an average winrate of 51.5% when playing against Sejuani with these items in his kit.
To have the highest likelihood of vanquishing Sejuani as Sion, Sion players should equip the Grasp of the Undying, Demolish, Conditioning, Overgrowth, Minion Dematerializer, and Approach Velocity runes from the Resolve and Inspiration rune sets. Of all the runes players used for Sion vs Sejuani counterpicks, this mixture of runes resulted in the best win rate. Notably, these runes provided a 51.5% winrate overall.
By default, tips, stats, and builds on how to beat Sejuani as Sion are given for all ranked divisions combined. If you want to narrow the statistics and builds to a specific division, you may use the selection menu located earlier in the counter matchup guide.