Koakoa

Koakoa was the last of the 3 Saucer Beasts that appeared in the OVA UFO Robo Grendizer vs. Great Mazinger. Its composition of pure energy and three Vegatron spheres makes it unique among Saucer Beasts.

Appearance
Koakoa was a manta ray-like being composed of energy with a red color scheme that has sparks going throughout its body and three purple eye-like Vegatron spheres.

Abilities and Weapons
Koakoa can fly and can shoot firey Vegatron beams from its eye-like spheres.

History
UFO Robo Grendizer vs. Great Mazinger:

While Kabuto Koji in the recaptured Great Mazinger was using Thunder Break on the energy core exposed from Barendos' Mothership to help fend off Grendizer and Great Mazinger, the core burst open and released Koakoa who immediately went to set Grendizer ablaze with a fiery beam unfazed by Duke Fleed seemingly skewering it with the mech's Double Harken. Koji fires a light Great Typhoon to put out the flames on Grendizer, Illiciting another fiery attack from saucer beast on himself as he uselessly skewers it with Great Boomerang. Next, a combined shot of Great Mazinger's Breast Burn and Grendizer's Hanjyuroku Storm destabilizes and cancels out Koakoa's electric body, with the spheres falling towards the previously trapped Grendizer despite its Hand Beam, Great Mazinger flew in and pulled Grendizer out of the way up before the spheres crash into the ship and explode, Killing Barendos and his crew, and ending their threat.

Trivia
Koakoa was very possibly named so for its use as an energy supply core for Barendos' ship