One of the Synthetic Beast from Episode 1 of Magne Robo Gakeen.
Octos was a Synthetic Beast who was with the Izawarians during their first attack on Earth. It attacks ships in the water until the Izawarians were defeated. After 2 million years, the Izawarians have restarted their attack on humanity. After sending another Synthetic Beast to attack the Tohoku Industrial Complex, Doctor Kazuki sends out his daughter, Mai, and a new man, Takeshi Hojo, in their two small giant robots, Mighty and Puraiza. When they aboard them after launch, Octos suddenly appears and grabs a hold of Mai’s Mighty. Takeshi uses Puraiza’s Knuckle Scramble to grab the tentacles that has a hold on Mighty. After using Puraiza Beam on Octos, Takeshi uses Puraiza’s Cross Cutter to slice Octos’ tentacle off, freeing Mai’s Mighty. After Mai and Takeshi merge into Gakeen and destroy Bardos, Doctor Kazuki has his ship, God Freedom, to go into flight mode. However, Octos appears and grabs a hold of the God Freedom and tries to drag it into the water. Doctor Kazuki calls for Gakeen to come help by reversing their combination. So the Mighty and Puraiza robots turn into arm gauntlets for Gakeen and they fly toward the God Freedom. When they arrive, Gakeen uses Puraiza Synthetic Fiber to stun Octos on the ship. Gakeen then uses it’s full power to spin and fly straight through Octos. Octos falls off the ship and into the water, allowing the God Freedom to fly off as Octos explodes in the water, finally destroyed.
Tentacles: Octos can use it's tentacles to constrict it's targets.
Adapted Swimmer: Being based on an Octopus, Octos can swim through the water.