Sivir's Boomerang Blade returns to her after reaching the max range, so you can shift position to hit enemies who would otherwise have evaded it.
Try saving Spell Shield for enemy abilities that can disable you such as stuns and roots.
Ricochet resets Sivir's basic attack timer on activation, so activating this immediately after landing a normal basic attack will maximize damage output.
Be wary of Cassiopeia's damage potential with Twin Fang when she has you poisoned.
Turn away from Cassiopeia when she is casting Petrifying Gaze to get slowed instead of stunned.
The stat comparisons shown on this page underscore several valuable Sivir against Cassiopeia counter statistics that may help us figure out the differences between the two. Sivir’s KDA ratio ([kills + assists] / deaths) of NaN is greater than Cassiopeia’s ratio of NaN, indicating that Sivir may be more central to her team's team fighting capability than Cassiopeia..
Sivir normally has a slightly smaller longest killing spree than her counter does. On average, she takes less damage than Cassiopeia. This often reflects differing health capacities, yet it can also illustrate that the one champion has less mobility and thus is unable to flee from additional damage when engaged or poked.
Both League champs are great champions. Both have their strengths, weaknesses, and counters. In League's current meta, Sivir usually fairs equally well when taking on Cassiopeia, with a 49.4% win rate. As a result, Sivir makes an ok counter for Cassiopeia.
While Sivir does have a lower winrate compared to Cassiopeia, when on opposite teams, Sivir also has a much lower difficulty level that makes her a less complex champion to learn and master. You should be careful when picking Sivir into Cassiopeia.
Furthermore, Sivir also has almost no amount of CC and other utility, a similar amount to Cassiopeia. This makes her just as valuable during team fights, especially when trying to counter champions with a lot of burst damage.
While there isn't a single best champion in League of Legends, in Sivir vs Cassiopeia matchups, Cassiopeia is the better champion with a similar win rate, less champion complexity, and a similar amount of utility to help out your team members during teamfights.
Sivir is a somewhat poor counter to Cassiopeia. You will do well by focussing your play on keeping up your gold and cs and taking out objectives. If you do that, you should be able to stand on your own as Sivir against Cassiopeia.
To truly master Sivir in order to counter Cassiopeia during both the early game and mid / late game phases of League of Legends, you should continue reading to learn a few extra tricks and insights into this matchup. If you mind the build and tips displayed here, you will grow your win rate by a lot and be closer to League of Legends pro players.
Sivir on average racks up a similar amount of CS relative to Cassiopeia. Champions who on average don't acquire much CS usualy don't require much CS to be valuable teammates, such as sup champs. They are capable of scaling properly off of their abilities and first items alone. Yet, champs with a lot of CS, such as hyper-carries, often have to have several high cost items to be effective. In either case, try to do better than the numbers shown here to do well.
The top items to have in your Sivir versus Cassiopeia build include Phantom Dancer, Kraken Slayer, and Navori Quickblades. When Sivir combined at least these three items in her build, she did a lot better vs. Cassiopeia than with many other typical builds. In fact, Sivir had an average win rate of 49.4% when countering Cassiopeia with these items in her kit.
To have the best probability of annihilating Cassiopeia as Sivir, you should use the Lethal Tempo, Presence of Mind, Legend: Bloodline, Coup de Grace, Biscuit Delivery, and Magical Footwear runes from the Precision and Inspiration rune sets. Out of all the rune builds players used for Sivir vs Cassiopeia counterpicks, this blending of runes resulted in the best win rate. In fact, these runes provided a 49.4% win rate overall.
By default, tips, stats, and builds on how to beat Cassiopeia as Sivir are given for all skill levels, merged. To scope the statistics and builds to an individual skill level, you can use the selection menu earlier in the counter matchup guide.