It seems to resemble something like a giant, dark blue whale or orca. It has two large fins or "wings", each ending with four square-shaped "claws." It has a deep blue body and a white chin area with two spikes protruding under it. Above each eye are two white spots. It has markings on its wings which sort of resemble the letter A with a circle on the top. It also has two small dorsal fins on its back with two stripes running horizontally below the fins. The tail seems tattered with four trails, the inner smaller than the outer. It also has a mouth full of rarely seen sharp triangular teeth.
As Primal Kyogre, it is more than twice its usual size and has a deeper blue body, as well as having a partially translucent body with a golden light glowing from within it, essentially emitting bioluminescence. It has light blue stripes on its body, instead of the usual red. The four tips on both of its large fins remain pure white. The usually opaque middle parts of its large fins become transparent, with red marks on the closer two tips of both its fins that resembles the letter H, its four white oval spots, and the part of the top center of its head have a circular marking, where the lines are linked to upper end of the larger oval spots, now also transparent, and they stop at the end of its tattered tail, where the middle of the four trailing parts have the same color as the glow on the majority of its body.
Kyogre does not evolve. However, in Omega Ruby and Alpha Sapphire, it is capable of changing into its Primal Form.
Before Generation 5, Kyogre was the only Pokémon to have the Drizzle ability.
Most of the legendary trio's and duo's look somewhat alike or at least have the same body class. However, all members of the Weather trio are completely different to one another. Kyogre is based on a killer whale, Groudon is based on a theropod dinosaur, whilst Rayquaza is based on a Chinese dragon.
Kyogre's moveset has an advantage over all other members of its trio. Water attacks on Groudon and Ice attacks on Rayquaza are super effective.
It is highly likely that Kyogre is based on the Leviathan from Judeo-Christian religion.
Kyogre and Groudon don't enter battle in their Primal Evolution forms when battling for you (Unless they're holding the Blue Orb/Red Orb respectively. If they are, Kyogre and Groudon will transform as soon as they're sent out).
Kyogre's name originates from the Japanese word Kai, which means ocean. Kyogre's name ends in ogre, due to it being large. Without the "Ogre" part, it spells out Kaiō, which means King of the Sea. Also, Kaiō is the first four letters of the word Kaiōsei which means Neptune, the Roman version of the Greek god of the sea, Poseidon.