Spread out when you see Sona so she can't make your entire team dance.
Kill Sona first, as she will heal up her team if left alone for too long.
The stats shown here emphasize some vital Yuumi vs. Sona counter stats that can help you interpret the distinctions between the pair. For instance, Yuumi’s KDA ratio ([kills + assists] / deaths) of NaN is better than Sona’s ratio of NaN, highlighting that Yuumi may be more central to her team's team fighting effectiveness than Sona..
Yuumi typically has a similar longest kill spree as her enemy does. Commonly, she takes less damage than Sona. This is usually reflective of different amounts of tankyness, but it can also hint that the champion with increased health has less mobility and thus is unable to flee from additional damage when poked or engaged.
Both League champions are great champions. Both champs have their pros and cons. In League's current meta, Yuumi usually loses when taking on Sona, with a 45.0% win rate. Therefore, Yuumi makes a poor counter for Sona.
While Yuumi does have a much lower winrate compared to Sona, when facing one another, Yuumi also has a lower level of difficulty that makes her a less complex champ to develop with. You should expect to face a difficult match when picking Yuumi into Sona.
Furthermore, Yuumi also has a great deal of CC and other utility, a similar amount to Sona. This makes her just as valuable during teamfights, especially when facing champions with a ton of burst damage.
While there isn't one best champion overall in League of Legends, in Yuumi vs Sona matchups, Sona is the better champion with a much lower win rate, less champion complexity, and a similar amount of utility to help out your team members during teamfights.
Yuumi is a bad counter for Sona. You will do well by focussing your gameplay on increasing your CS and taking out objectives. If you are able to do that, you should do very well as Yuumi against Sona.
To truly master Yuumi in order to counter Sona during both the early game and mid / late game phases of League of Legends, you should keep reading to gather a few extra lessons on this matchup. If you pay attention to the build and suggestions displayed above, you will increase your win rate by a lot and be that much closer to League of Legends pro players.
Yuumi usually racks up less CS relative to Sona. Champions who typically don't acquire much CS often don't have to have much CS to be effective, such as support champions. They are capable of scaling properly off of their abilities and first items alone. Yet, champs with large amounts of CS, such as hyper-carries, often require several high cost items to be effective. In either situation, try to do better than the numbers shown on this page to do well.
The most important items to use in your Yuumi versus Sona build include Mikael's Blessing, Ardent Censer, and Moonstone Renewer. When Yuumi used at least these three items in her build, she performed significantly better when facing Sona than with many other commonly used builds. In fact, Yuumi had an average winrate of 45.0% battling Sona with these items in her kit.
To have the highest probability of coming out on top against Sona as Yuumi, Yuumi players should equip the Summon Aery, Manaflow Band, Transcendence, Scorch, Font of Life, and Revitalize runes from the Sorcery and Resolve rune sets. Out of all the rune builds players chose for Yuumi vs Sona battles, this sequence of runes yielded the highest win rate. In fact, these runes provided a 45.0% win rate overall.
If you want to see Yuumi versus Sona tips and counter builds for a a distinct player tier, feel free to choose one from the selection menu shown above. At first, the statistics and build suggestions displayed are calculated using every game with data with both champs.