Gnar Runes explained
There's one set of runes for Gnar on patch 14.9 that is the clear favorite for LoL players and pros alike. The best Gnar rune paths on the position 
Top are 
Precision as the primary path and 
Resolve as the secondary path with a pick rate of 99%. Besides picking runes on Gnar you should learn how to play Gnar and if you are interested in pro matches take a look on how a pro builds Gnar. If you want to discuss 
Gnar then you should visit the champion subreddit.
Gnar runes from primary path
Precision improves attack and sustained damage on Gnar troughout the match. Most of high elo players – and our LoL pros in the the major regions – have agreed that Fleet Footwork is the best keystone rune to run on Gnar. This keystone rune generates you a lot of sustain and increases your survivability against poke champions in lane. Other primary runes on Gnar are Triumph, Legend: Alacrity and Last Stand.
Triumph restores on Gnar a part of missing health and award bonus gold, if a champion is killed. Legend: Alacrity grants additional attack speed to Gnar. With Last Stand you deal more damage while you are at low health.
Gnar runes from secondary path
When it comes to your secondary path, most Gnar players prefer to go with Resolve. Resolve empowers the survivability of Gnar and increases the tankiness. On the Resolve path, the best runes for Gnar are 
Overgrowth and 
Bone Plating.
Overgrowth increases your maximum amount of health. Bone Plating make Gnar overall tankier, by decreasing the amount of poke damage in the early game.
FAQ for Gnar Runes
Which is the best keystone rune on Gnar?
The best keystone rune on Gnar is Fleet Footwork. This Gnar runes setup is then referred as Gnar Fleet Footwork.
What runes does Gnar use?
Runes from the paths Precision and Resolve are the most used runes on Gnar. For the exact pick rates of Gnar runes used, you have to study the rune distribution presented.