Now, I had plenty of time today to think these through. Hopefully they are balanced enough.
Akron : Gryphon. When summoned, flies in from the sky. Slashs at enemies. Deals minor to moderate damage. When it leaves, enemies have Slow cast on them.
Balzak : Giant Stingray. When summoned, battleground fills with water, and Balzak appears. Casts Cure and Esuna on entire party. (Goes to Cura and Curaga after levels)
Blazer : Lion on fire. When summoned, the battleground is set on fire. He roars and the enemies are hit with Fire (or some variation). Minor to moderate damage.
Fenrir : Large wolf like dog. When summoned, emerges from the earth behind the enemies. Howls long and loud. Howl casts Silence and disorients the enemies, confusing them. Deals minor normal damage due to intensity of the howl. Can be used once per battle.
Kraken : Giant Squid. Water fill the battle ground and the Kraken emerges. Squeezes the enemies with tentacles. Minor to moderate damage.
Nazewrath : Giant. Just a giant. Takes time to summon. A lot of time. When he is summoned, he falls from the sky, shaking the ground. Casts Meltdown pn enemies and Aura on party members. Used once per two battles.
Orochi : Giant 8 headed dragon. When summoned, a hole in the ground opens up, and screams are heard. Each head shoots a different offensive magic, but only two heads attack per summon.
1st head : Fire (or a variation)
2nd head : Blizzard (or a variation)
3rd head : Thunder (or a variation)
4th head : Quake
5th head : Meteor (minor)
6th head : Ultima (minor)
7th head : Water
8th Head : Random Offensive Magic
Phoenix : A huge bird on fire. When summoned, it emits a loud screech. It then flies from the sun to the battleground. Unleashes a large stream of white fire and causes moderate fire damage to the enemies. Can only be used once every two battles. Heals all status ailments, and minor - moderate injuries. Does not revive.