River F9 is a Mechanical Beast made by Dr. Hell and commanded by Baron Ashura from Mazinger Z.
What it does[]
Anime[]

Those chest things are nips right?
Koji fights this in ep 61 where they (someone fill the rest in. I never saw it)
Manga[]

They're crusin for chix.

2 hedZ! r bettur den wun!! ahuhuhuh!
After Baron Ashura found Schtroheim Heinrich he/she sent River F9 to bust his home. But Schtroheim sent Donau Alpha 1 out. Schtroheim somehow snuck aboard Ghoul and confronted him/her. After revealing his motives, He tried to stop Ashura from sending the incomplete Donau out but Ashura shredded him with machineguns and threw his bod out. B4 he bites it, he tells Lorelei he made her as the Heart and mind of Donau Alpha 1 and couldn't hand her over to Dr H (kind of a reverse Astro Boy) and tells her his last wish is for her to fuse with Donau and beat Mazinger. Despite Shiro Kabuto's attempts to save her, she does it and goes after Ashura for wasting her pop. She busts River F9's head with her head tentacle but River shoots back and reveals a 2nd head(not THAT kinda head(although go nagai probably would've done it(look at Zork from Yugioh))). River shoots Donau with head things and but is grabbed by Donau's head tentacle around da neck and slammed into da ground, bustin off its head. River extended spike tentacles to penetrate Donau (whos really a little girl) but its countered by Donau and she blows River apart with rockets. and then... he died... ahhhhhhh!!