Kyogre @ Blue Orb
Setting up for competitive and in-game sweeping
You should put ice beam on Kyogre. Kyogre is a water type so it is weak to grass types. This will cover that weakness and allow you to beat dragon and flying types as well. Also, Kyogre has a better special attack stat and ice beam is a special attack. This is why I would say you should put ice beam on Kyogre.
Do you hate dragons more or like general good damage? For dragons, ice beam, if good damage, earth quake, but not for double battles or royales, for those ice beam.