Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
This Janna build is intended for 3v3 only because any Janna that doesn't shield properly is considered weak in 5v5. In 3v3 there is much less ganking so that Janna has more room to apply her less supportive strategies.
The key to this build is staying alive by not allowing Janna to come into body contact with enemy champions. Janna that stays alive through serious assassination attempts can be really frustrating to your opponents and this will give time for your teammates to act.
Another key element of this build is Howling Gale spam, which is why reaching 40% CD reduction earlier is a priority. Howling Gale is the most irritating non-ultimate ability to enemy champions as it both helps you clear lanes and at the same time gets your opponents thinking about it a lot.
If played properly this build can get you a couple of levels ahead of everyone else and give a bad leveling experience to your opponents.
Pros / Cons
Demand on precision
9xGreater Mark of Insight - 8.55 magic penetration
9xGreater Seal of Force - 0.90 ability power (16.20 at 18)
9xGreater Glyph of Insight - 5.13 magic penetration
3xGreater Quintessence of Insight - 5.67 magic penetration
This will give you 19.35 total magic penetration which will bring down the initial magic resistance of enemy champions from 23%(30 magic resistance) to 9%(30-19.35=9.65 magic resistance). This converts into a serious ability damage increase as 23%-9%=14% of your ability damage is not resisted.
Presence of the Master and Quickness are two masteries that are a must to increase survivability of Janna. The two summoner spells combined with Boots of Mobility can give Janna a near immortality if care is taken.
Greed and Awareness are essential for staying ahead of your opponents as the Howling Gale and Zypher leveling priority will get your Janna the needed damage output to be able to harass.
There is no Sorcery and Archaic Knowledge primarily because Archaic Knowledge will give you only the equivalent of around 1.4 magic penetration after the flat magic penetration on your runes is applied. That is, the leftover 9.65 magic resistance on enemy champions will go down by only 15%(~1.4). On top of this, Sorcery is only 3% cooldown reduction in contrast with 6% you get from Intelligence.
Defense tree is empty because Janna's survivability is dependent solely on her mobility.
Philosopher's Stone early in the game will give you room to lane with a topped off health bar and decent on-the-go mana refill while Boots of Mobility will start you off on the path of survival(and getting your opponents pissed). Greed mastery andPhilosopher's Stone gold bonus will give you 36 gold each minute which is the equivalent of gold you get from killing a siege minion(30g) + 20%(6g). Also, while you are getting Philosopher's Stone it is probably a good idea to start buying midmap wards against bushwhack-happy opponents.
Ideally, you should get3 mana pots after theBoots of Speed. Use them to stay in lane longer at the start of the game. After that, if you have spare gold from buying items gettwo more mana pots. You should stop buying pots and start saving after you get thetwo Meki Pendants(24 mana/5 sec is enough to keep you from running dry all the time + you will often need to get back to your base anyhow).
When you get theFiendish Codex and have spare 250 gold after buying consequent items get oneElixir of Brilliance. Use it when you get back in the fray. Continue buying the elixir with your spare gold whenever you need to refresh the cooldown. Don't worry if you don't have it up all the time and have no gold to buy a new one: items are more important than the elixir.
Later in the gameHaunting Guise will give you the total of 40 flat magic penetration. If your opponents still have 30 initial MR(without MR from gear/runes/masteries/passives) then your 40 magic penetration will actually take all of the 30 MR off(that is, 23% absorption of your magic damage) and on top of this increase your ability damage by 9%. This would not be the case if you had percentile magic penetration(ex. Archaic Knowledge and Void Staff) as it doesn't reduce MR below zero and is always applied after the flat magic penetration is applied.
Unlike other Janna builds this Janna can afford to be a harasser from level 1. Boots of Speed, the two summoner spells and midmap ward will give her enough room to avoid death. However, you should still concentrate on killing enemy minions with your Howling Gale.
Rank up Howling Gale and Zephyr as much as possible and don't worry about the other two abilities. Use Zephyr to harass enemy melee champions and avoid getting below 2/4th to 3/4th of your health bar. Keep your enemies thinking where the Howling Gale will hit. A couple of hits with your staff + Howling Gale hit + Zephyr can get your opponents worried and running. But don't get too cocky as your main priority is leveling up. Watch out for the bushes.
Often, there are ranged champions that will try to harass you instead. In that case, stay far behind and throw in a Howling Gale every now and then. Feeding your enemies with Janna is the easiest thing you can do.
You should always be aware of the slows and stuns enemy champions can unleash on you. If there is nothing that impedes your movement then Flash is usually enough to save your life. However, don't be afraid to use both when you get severely ganked.
Again, this build is not intended for 5v5. Janna as it is is a highly nerfed champion rarely played by anyone. If you are the kind of person who enjoys achieving the impossible then this is the build for you.