Azir Runes explained
There's one set of runes for Azir on patch 13.24 that is the clear favorite for LoL players and pros alike. The best Azir rune paths on the position 
Mid are 
Precision as the primary path and 
Inspiration as the secondary path with a pick rate of 25%. Besides picking runes on Azir you should learn how to play Azir and if you are interested in pro matches take a look on how a pro builds Azir. If you want to discuss 
Azir then you should visit the champion subreddit.
Azir runes from primary path
Precision improves attack and sustained damage on Azir troughout the match. Most of high elo players – and our LoL pros in the the major regions – have agreed that 
Conqueror is the best keystone rune to run on Azir. This keystone rune provides additional power in the later stages of a game. As soon as Conqueror is fully charged, Azir deals additional damage and gains life steal. Other primary runes on Azir are 
Presence of Mind, 
Legend: Alacrity and 
Coup de Grace.
Presence of Mind helps Azir with the mana problems by restoring missing mana, if a champion is killed. Legend: Alacrity grants additional attack speed to Azir. Azir deals with Coup de Grace more damage to targets with low health.
Azir runes from secondary path
When it comes to your secondary path, most Azir players prefer to go with Inspiration. Inspiration opens creative opportunities on Azir troughout the match. On the Inspiration path, the best runes for Azir are Biscuit Delivery and Cosmic Insight.
Biscuit Delivery is a great rune for laning as it gives additional health and mana, which can help in more aggressive lanes. Cosmic Insight grants summoner spell and item haste.
FAQ for Azir Runes
Which is the best keystone rune on Azir?
The best keystone rune on Azir is Conqueror. This Azir runes setup is then referred as Azir Conqueror.
What runes does Azir use?
Runes from the paths Precision and Inspiration are the most used runes on Azir. For the exact pick rates of Azir runes used, you have to study the rune distribution presented.