Shin Getter Robo tai Neo Getter Robo

Both feature the struggle of humans against non-humans, a mecha with god-like powers, and an emphasis on drills as weapons, though with Tengen Toppa the drill is symbolism representing humanity moving past obstacles and climbing higher - or a sexual metaphor in some cases. Both anime also feature hotblooded heroes and combine humor with drama. Although, Tengen Toppa features a set of romantic subplots as well. 

Like Getter Robo Armageddon, this is another continuity reboot of the original Getter Robo Go manga.