The Gwen build for Top is Riftmaker and Conqueror. This LoL Gwen guide for Top at Platinum+ on 13.18 includes runes, items, skill order, and counters.
50.5%
(+0.6%)
53.1%
(+0.5%)
3.3%
(+0.1%)
2.9%
(+0.8%)
832
(+7)