The Diana build for Jungle is Hextech Rocketbelt and Conqueror. This LoL Diana guide for Jungle at Platinum+ on 13.24 includes runes, items, skill order, and counters.
Diana Counters
51.4%
(+0.7%)
63.2%
(+1.3%)
5.5%
(+0.6%)
2.4%
(+0.3%)
722
(-15)
