Find and build a VGC team, learn how to use it, then unleash it on Kieran.

(I think that's the best way about it)

I dont do vcg so i dont want to do that. My current team is Meowscarada, Tinkaton, Miraidon, Chien-Pao, Ting-Lu, Chi-Yu. That's the team I'll use. Everyone is lv 100 except Miraidon who's like lv 88 or smthn

My whole team is legends except 1 i have koraidon ogerpon fire mask terapagos peacharunt iron bolder and alola ash cap pikachu

Umm...I guess chien Pao meowscarada and attempt to outrun and out damage everything with them both?

Quick Tip: Kieran has built-in Follow Me effect on Ogerpon. So long as Ogerpon is on the field, he’ll prioritize attacking her.

Ogerpon can learn both Spiky Shield and Protect.

So long as you have Ogerpon out, you can safely bring out an attacking Pokémon and freely knock out his Pokémon.