Karthus can cast spells for a short duration after he is killed. Move away from his corpse to be safe.
Make sure you always have enough health to survive Requiem, even if you have to go back to the base more frequently to heal.
The stat comparisons provided here show several critical Seraphine against Karthus counter statistics that may help us distinguish the differences and similarities between the pair. As an example, Seraphine’s KDA ratio ([kills + assists] / deaths) of NaN is better than Karthus’s ratio of NaN, showing that Seraphine may be more central to her team's team fighting effectiveness than Karthus..
Seraphine often has a slightly smaller longest killing spree than her counter does. Commonly, she takes less damage than Karthus. This is usually reflective of different amounts of tankyness; however, it can also hint that the champion with higher HP has less agility and thus is unable to kite away from additional damage when engaged or poked.
Both LoL champs are great champions. Both have their strengths, weaknesses, and counters. In the game's current meta, Seraphine usually wins when taking on Karthus, with a 52.5% win rate. Thus, Seraphine makes a good counter to Karthus.
While Seraphine does have a higher winrate compared to Karthus, when they face off with one another, Seraphine also has a much lower difficulty level that makes her a less complex champion to pick up and master. You don't need to be too worried when picking Seraphine into Karthus.
Moreover, Seraphine has a lot of utility and CC, a similar amount to Karthus. This often makes her just as valuable during team fights, especially when facing champions with a ton of burst damage.
While there is not one best champion in League of Legends, in Seraphine vs Karthus matchups, Seraphine is the better champ with a noticably higher win rate, less champion complexity, and a similar amount of utility to help out your allies during team fights.
Seraphine is an above average counter to Karthus. Focus your play on increasing your gold and cs and clearing objectives. If you do that, you should hold your own as Seraphine against Karthus.
To truly master Seraphine in order to counter Karthus during both the laning and mid / late game phases of League of Legends, you should keep reading to pick up a few extra tricks and insights into this matchup. If you pay attention to the build and tips presented above, you should increase your win rate by a lot and be that much closer to League of Legends pro players.
Seraphine typically gets a similar amount of CS as Karthus. Champions who typically don't take much CS often don't require much CS to be valuable teammates, such as support champions. They are capable of scaling well off of their skills, stats, and first items alone. Yet, champions with large amounts of CS, such as hyper-carries, typically need several high cost items to be effective. In either case, try to do better than the values shown here to do well.
The ideal items to have in your Seraphine versus Karthus build consist of Seraph's Embrace, Dream Maker, and Moonstone Renewer. When Seraphine bought at least these three items in her build, she performed a lot better when fighting Karthus than with many other typical builds. In fact, Seraphine boasted an average win rate of 52.5% battling Karthus with this build.
To have the highest likelihood of annihilating Karthus as Seraphine, Seraphine players should use the Summon Aery, Manaflow Band, Transcendence, Gathering Storm, Triple Tonic, and Cosmic Insight runes from the Sorcery and Inspiration rune sets. Of all the rune combinations players picked for Seraphine vs Karthus fights, this combination of runes resulted in the best win rate. Moreover, these runes provided a 52.5% winrate overall.
By default, tips, stats, and builds on how to beat Karthus as Seraphine are presented for all ranked divisions. If you want to scope the statistics and builds to a specific rank, you may use the selection menu located above.