I like the gorebyss angle. Would probably also play huntail so that you can control flow of energy to either hand or discard, makes you more adaptive. Draw engine would be revavroom (wow I just got the joke!!), naturally. And then with all those stage 1s either Hyper Aroma or Precious Trolley. Supporter of choice would be Explorer's Guidance. The deck practically builds itself---but would it be good?
Whirltide Kingdra definitely synergizes, but its a stage2 and its attack is luck-based, makes me nervous fam.
I could also see this Kyogre being included as one-off in a Misty's Gyarados deck as an optional mid/late game attacker if you cant get Sacred Ashes and a Snek.
And then theres that Gyarados that discards 5 of your own cards when it evolves. Is THAT ever the play? Self-mill all the way to nuke town? And then you play Hilda + Ignition Energy so you can actually use the Gyra's attack , 200 and discard energy from active is pretty powerful. Seems kinda sick if its consistent, TBH