Trundle Runes explained
There's one set of runes for Trundle on patch 15.12 that is the clear favorite for LoL players and pros alike. The best Trundle rune paths on the position 
Jungle are 
Precision as the primary path and 
Inspiration as the secondary path with a pick rate of 98%. Besides picking runes on Trundle you should learn how to play Trundle and if you are interested in pro matches take a look on how a pro builds Trundle. If you want to discuss 
Trundle then you should visit the champion subreddit.
Trundle runes from primary path
Precision improves attack and sustained damage on Trundle troughout the match. Most of high elo players – and our LoL pros in the the major regions – have agreed that 
Press the Attack is the best keystone rune to run on Trundle. Trundle has a very easy time activating this rune with basic attacks which synergises well with Press the Attack’s damage increase once activated. Other primary runes on Trundle are 
Triumph, 
Legend: Alacrity and 
Coup de Grace.
Triumph restores on Trundle a part of missing health and award bonus gold, if a champion is killed. Legend: Alacrity grants additional attack speed to Trundle. Trundle deals with Coup de Grace more damage to targets with low health.
Trundle runes from secondary path
When it comes to your secondary path, most Trundle players prefer to go with Inspiration. Inspiration opens creative opportunities on Trundle troughout the match. On the Inspiration path, the best runes for Trundle are 
Magical Footwear and 
Cosmic Insight.
Magical Footwear allows Trundle to focus on those essential core items without the need to spend the additional 300 gold on boots. Cosmic Insight grants summoner spell and item haste.
FAQ for Trundle Runes
Which is the best keystone rune on Trundle?
The best keystone rune on Trundle is Press the Attack. This Trundle runes setup is then referred as Trundle Press the Attack.
What runes does Trundle use?
Runes from the paths Precision and Inspiration are the most used runes on Trundle. For the exact pick rates of Trundle runes used, you have to study the rune distribution presented.