>>20624850You really can't. Water Spout kills Groudon in one hit even in the sun, unless Groudon fully invests in both HP and Sp. Def., which is, for one, stupid, and second, it still holds a 6.3% chance to OHKO, meaning even if it doesn't faint on the first turn, it'll die to anything on the second.
Obviously, Groudon can't do anything back, since the only attack it has decent against Kyogre is Solar Beam, and given how Groudon is supposed to be a physical attacker, it's pretty much a waste of a move. Earthquake is the only move that does more than half damage to Kyogre, but with lower speed, it again is pretty unlikely to hit Kyogre a second time.
Now, with its primal adding even more of a weakness to Water, the only thing that can save Groudon is if he gets an ability that weakens/nullifies Water attacks, because otherwise, the story becomes even more nonsensical.
In short, yeah, the conflict between Groudon and Kyogre is believable only lore-wise.
