I started playing League at the same time that Yuumi debuted. She was new, I was new so I decided to make her my main. She is a very unique type of character with a very unique kit, I've been having a lot of fun with her and I hope you do too!
Every time a patch changes something around her, be it an item, runes or even her passive, it is necessary to adapt your behavior as a player, she is very sensitive to changes and this time....a lot of things changed! Let's take a look and get the most out of it.
I decided to make a guide with not only the items to buy or runes to build but also with some insights on how to behave in certain situations and how to properly use the passives of your items. I could expand each topic but I believe that small and direct phrases are best for the reader. If you have any questions or want me to explain something better please leave a comment!

- You don't need potions so it's possible to start already with a Control Ward

- Imperial Mandate and Moonstone Renewer need the same basic items, you can start building them and make the decision later. Remember that you can only have ONE MYTHICAL ITEM. If, for any reason, you want to change your build you need to sell your Mythical and buy the other one. This is viable in very specific situations but note that you are going to lose 30% of the gold applied when selling.

- Start with Bandleglass Mirror, Ap and Mana Regen provides more value for Yuumi when compared with Health from Kindlegem

- Always prioritize the Mana Regen segment of the items that you are building. If you are in doubt of which Legendary item to buy next, think about getting a Forbidden Idol first since it is very useful in itself and serves as part of many important items for Yuumi such as Redemption, Ardent Censer, Mikael's Blessing and Staff of Flowing Water.

- This goes for almost all support heroes, buy Control Ward!! Even if you already have one on the field, always keep another with you. Vision can vastly help your jungler and help you avoid getting ganked early on.

- Avoid locking your 6 slots in a way that you have no space for Wards. Sometimes a well positioned Control Ward has more value than a Faerie Charm

- There is a new item called Vigilant Wardstone, basically it increases the amount of wards that you can place and it let you hold 3 Control Wards. I still have mixed feelings about building this item

This is what my Item Set usually looks like. I highly recommend making one, this reduces a lot the time spent on the shop, organize the way you think and your choices. Try making one for the heroes that you use the most, especially since we have so many new items with new icons its easy to get lost

- Your W You and Me! activates Summon Aery, and Aery counts as a no cost shield for Flowing Water and Ardent Censer. This is important during objectives where you can't normally recover mana due to the lack of enemy champions. You can activate the increase in attack speed by jumping between your teammates.

- Try to use W on your jungler during the initial Red/Blue (you can do this two times normally), this way the free shield from Aery can absorb some damage and you can protect him without expending mana or having to start with E Zoomies. The optimum way is AA-> W with Aery -> Go to Adc -> Wait for Aery -> W back to Jungler and proc Aery again -> Floor and AA or W Back to Adc. The increase in Ap/Ad for them compensates one Auto Attack from you

- At the beginning of the Lane Phase mana will be a problem so avoid going all trigger happy with Prowling Projectile and Zoomies. Wait for your passive and hit the enemies with your auto attack, your passive plus Presence of Mind are crucial for having a healthy lane phase

- Since now we have so many sources of mana regen it is possible to stay on your lane longer. If your adc dies too soon you can think about staying, helping your jungler for a while or even use this time to ward the drake

- If you sense that your death is inevitable do not just give up, try to use your last energy to place a ward

- Always keep track of your passives. The cooldown of Feline Friendship is somewhat high so if you are going to take the risk of auto attacking, at least wait for your passive to be active and recover some mana and get the shield from it

- Manaflow is important and you should stack it as fast as possible. If you see that the rune is in cooldown maybe its best to wait a little before you fire another Q. The cd can be seem on the right part of your passives

- The same goes for Aery, keep track of where she is and act accordingly, you can see if she is with you on your passives, and remember that your W You and Me! activates her. This is important for when you need to heal your teammates and don't have the mana for it, or your E is on cooldown.

- Anti-Healing cuts your healing by a lot (40%~60%) and there are many ways for your enemies to apply that on your teammates, but remember....Anti-Healing doesn't affect your shields! so use Aery and your passive as much as possible when dealing with enemies that rushed anti-healing items

Summon Aery

✦ She protects, she attacks and most importantly she is free! You can cast her without any mana cost just by using your W You and Me!. ✦ Since Aery is a shield every item that needs you to "heal or provide shield" for a teammate can receive its bonus. Just by jumping between heroes you can activate Ardent Censer and Staff of Flowing Water, this is very important during objectives, Drakes and Baron ✦ When you heal someone Aery needs to leave you, go to that person, and come back, if you pay attention you can even see her floating around, but since Yuumi is as close as possible to the target Aery doesn't need to waste time moving around

Manaflow Band

✦ Another crucial rune for Yuumi. This hero is very mana dependent and Manaflow is perfect for her, try to stack this as fast as possible to receive not only an increase of Max Mana but also Mana Regen ✦ Pay attention to the passive, if you want to stack it fast it is important to see if he rune is on cooldown. Sometimes its best to wait 1 or 2 seconds before firing another Q. ✦ You Q is the only viable source of stacks early on, try not to miss. If you miss too much you are soon gonna be running out of mana

Transcendence

VS

Absolute Focus

✦ Gives Ability Haste in two doses, level 5 and level 8 which by itself is pretty good, but also after takedowns you gain 20% cd reduction of non-ultimate abilities. During long teamfights this is very important

✦ Since most of the time you are going to stay above 70% Health this rune is also viable to consider

Scorch

VS

Gathering Storm

✦ Very good early on, improves by a lot the damage of your Q. Consider this rune if you want to follow the Poke Build but keep in mind that Mid-Late game this rune is not going to make a lot of difference

✦ As the name implies this rune starts very weak, providing only a little bit of AP but later on it becomes very strong providing as much AP as some legendary items

Presence of mind

✦ I would go and say that this rune is as important for Yuumi as Summon Aery and Manaflow Band. Providing Mana Regen without increasing Max Mana is perfect for this hero, since her E Zoomies will not have its cost increased. One big problem for Yuumi is mana management during long battles and since this rune also restores some mana after participation on a takedown, you can last considerably longer.

Coup de Grace

VS

Cut Down

✦ Yuumi naturally has a very small health pool so this rune fits perfecly this hero, or at least it used to. Now many vital items for her increase health, reducing the impact of the rune. I would pick this rune if you are against tanks like Leona or Alistar

✦ I find myself using Coup de Grace more since it provides just enough damage to kill some enemies that are trying to escape with an already low health

I've been playing with her for a while in this new patch and I reached two main builds, one focused on healing and buffs and another based on poking and damaging. Remember that we can only choose ONE MYTHICAL ITEM and the builds heavily revolves around them.

One very singular thing about Yuumi is that she doesn't need to buy Boots and in this season having one free slot for one more Legendary item is a great thing since the Mythical item can provide her with 5 passives instead of the normal 4 for other heroes.

Our first build uses Moonstone Renewer as the Mythical item and increases Starlit Grace’s heal by 10 per Legendary item that you possess and each second spent in combat with champions grants 7% heal and shield power, stacking up to 5 times for maximum of 35%, this becames incredible powerful during long fights. Let's take a look a how the MoonStone works and the Legendary companions for it.

When affecting champions with attacks or abilities in combat Heal (60hp base) the nearby allied champion (excluding yourself) with the most missing health(2 sec cooldown)

every time you heal or shield someone you and him receives 20 ability haste and 25-45 AP (based on target’s level) for 4 seconds

every time you heal or shield someone you and him receives 10-30% attack speed and 5-20 bonus magic damage on-hit.

Put all this together and....well...embrace the buff and healing machine that you were born to be! With every Q, AA or Ult you are going to heal a teammate, provide atk speed, ability haste, bonus AP and a bonus magic damage. Remember that the Moonstone Renewer has a cooldown of 2 seconds, always check your passives to see when is a good time to hit your Q again or to get out and AA.

Keeping in mind that with your Zoomies and Ardent Censer you increase by a lot your teammate's Attack Speed, but there is one very particular case of a hero that cannot have its Attack Speed normally increased and that is Jhin. Instead of getting Attack Speed he will transfer part of it directly into AD, that being said, when you are connected to a Jhin try to use Zoomies during his ult or during his last bullet, he is going to deal A LOT of damage his way.




Our second build revolves around another Mythical item called Imperial Mandate, this one increases 15 AP for every Legendary item, again let's take a look at how it works.

Every time you hit an enemy with an ability that Slows or immobilize you deal bonus damage and mark them for 4 seconds. When an ally hit this marked champion he deals another bonus magic damage and both of you gain 20% bonus movement speed. This is perfect for Yuumi since her Prowling Projectile applies natural slow so you will always proc this passive with your Q

This item shines especially against healing enemies like Soraka, Senna, Sona, Nami, etc. Aside from them, a lot of new items and builds possess vampirism or Omnivamp (life steal) so this item could be very powerful during lane phase and late game. Considering the fact that your ultimate can apply 60% Grievous Wounds this can turn the tables and diminish the power of an enemy healing support or an Omnivamp build

In certain circumstances when the moon is right, this item has great value on Yuumi, considering the fact that you can use it while connected, leading to some great combos. You can use after you ult to keep someone rooted, so help your teamates to escape someone or even as an alternative cc. Yuumi is very mana sensitive and having a no-cost skill is very much appreciated.

It isn't an ideal item, since Yuumi needs more Mana Regen instead of Max Mana, but still can have its uses. The most important thing to remember is that your W with the shield from the passive activates the Tear, so you can easily farm the Tear without spending mana and pretty fast

Solari has two qualities for yuumi, the first one is against burst enemies like Khazix and Rengar, your healing is not going to save your teammates but your shield might. Other than that is the fact that Solari isn't affected by your stats, so even a weak Yuumi can fully use the item. As stated before, shields are not affected by anti-healing making Solari even more efficient when the enemy team is fully built around it

Empowering or protecting another allied champion (excluding yourself) grants both allies 25% movement speed over 1.5 seconds, and aside from this the mythical passive grants 5 ability haste per legendary item. This item is great for fast paced games just remember that improve your healing abilities like Moonstone. The passive doesn't work for long, only 1.5s, and keeping this up with Yuumi isn't very easy or cheap.

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Bop 'n' Block (Passive)

✦ You will always need mana and shield so pay attention to this and try to activate it as much as possible, but take care of WHEN to exit and auto attack. In many situations it is a high risk high reward choice that you have to make, so wait for the enemies to use their cc and get your bubble shield. ✦ Sometimes enemies like to save their cc while waiting for you to exit, if they do this you are going to starve on mana pretty soon. If it comes to this situation, one option is to fake an attempt to get the shield, get back to your teammate and exit again after they failed to get you. The cooldown of your You and Me! is going to start but at least you made them waste mana and cooldown while you are getting shield and mana. Sometimes when you do this you are open to get hit by some auto attacks but remember that your shield will help you to survive. It all comes down to mind play at this point and you need to measure risk-reward opportunities. ✦ During late game teamfights is important to keep track of crowd controls that could stop you so wait for them to use and get out to get your precious mana and shield. ✦ On an important side note anti-healing items do not affect your shields, this is vital to many games where the enemies rush items to counter you. Remember that mages also have a new and cheaper item that provides anti healing, Oblivion Orb has a new passive that applies Grievous Wounds

Prowling Projectile (Q)

✦ This is your main source of damage and depending on the build it is also your way of getting mana with Presence of Mind and healing with Moonstone Renewer. ✦ It is very costly early on to fire this this the mana cost is fixed BUT this is also a blessing since you can upgrade it and keep the fixed mana while increasing damage and reducing cooldown ✦ It is crucial to let the projectile fly for 1 second before hitting an enemy. Normally you will only deal a little amount of damage based on a fixed value, 30% of your AP but if you let it fly for 1 second the fixed damage increases a bit, instead of 30% it is now 40% of your AP, plus a percentage of the target's current Health and you slow the enemy for 1 second by 20%, this is important if you are using Imperial Mandate ✦ You Q also works like this for Drakes and Baron, instead of firing directly forward try to make a long turn and hit it after he skill gained the increased damage.

You and Me! (W)

✦ The most important thing that you need to remember is that this ability generates free shield from Summon Aery ✦ You can freely go from one teammate to another without any cooldown but keep track of the little yellow bar on top of your skill, this shows a secondary cooldown where if you touch the ground you will not be able to You and Me! again until this runs out ✦ The fact that this ability generates shields from Aery means that it also activates items based on "Healing or shielding an ally (...)" such as Ardent Censer and Staff of Flowing Water. During baron, drakes or situations where you need to save mana you should use this in your favor and keep jumping between your teammates while activating passives and Aery ✦ On a cool side note, if you have Fiddlesticks in your party you can use You and Me! on the Scarecrow Effigy. This is incredible when you need to fake a gank, escape something or simply getting a better angle for your ultimate

Zoomies (E)
✦ Healing at its prime, pure and simple, but you also increase your teammate Attack Speed and Movement Speed, this used on the right time can immensely help the flow of battle. ✦ If you are low on mana try to activate this skill together with Aery a few seconds before your teammate is hit by any enemy skill, this way the shield will take part of the damage while the healed health is untouched.

Final CHapter (R)
✦ Many times this ultimate can turn a bad situation into a good opportunity. You can use it defensively to escape a fight or to create opportunities to start one. ✦ Remember that you can still use You and Me! and Zoomies while ulting, it means that you can fly between your teammates and root even more enemies instead of focusing in only one, also remember to Heal if necessary

- Thanks StrikeX114 for helping me fix an important typo