Download full size infograph here.
Kyogre is back! The elusive blue, sometimes purple whale, coming to raids near you. Landing this whale will help in PvP for sure, and has a place atop Master PvP as well.
What to use? Water typing makes grass and electric your go to attackers. Electric is generally the harder hitter, my lucky shundo Electivire always gets a spot, paired with an electric mega on the field and we are in business! I really hope you picked up a good Zekram while they were around, should probably trade for one if you can.
Go to the official counters page for a complete list, including shadows and megas to see how your Pokémon perform.