Space Runaway Ideon (along with devilman) is pretty much the direct inspiration for Evangelion. Anno drew heavily from Ideon for the tone and style of Evangelion, and it shows. Both shows have very bleak worlds dominated by potentially apocalyptic mecha that are just barely understood. Both end with the effective end of the universe, and both deal heavily with philosophy.
Ide and Zillonium are things that help humanity when humanity still can't completely understand or control them. Ide is a more complex legend come to life, an energy that is like a god, with absolute power and free will. Zillonium is only a mineral that helps the survival of any species.
Both series have a special wick that is kind of supreme being legendary
(especially the Ideon is a God) and also famed special ship war (Solo Ship in Ideon / The Shank in Tobikage).
In both series the protagonists flee through space and mid of series they return to Earth
but are not accepted.
however the contents are different, Sapce Runaway Ideon is one real robot series while Tobikage is a super robot series.
Harlock and his crew are practically banned from Earth while they fight to protect it from an alien race called the Mazone, which resemble beautiful women in appearance. In Ideon the group who discover the "Solo Ship" and the Ideon end up being pushed away from their homeworld as well, with nowhere to run while being chased by the mysterious Buff Clan that resemble humans themselves. In both shows, the casts home is ... their spaceship, with nowhere else to go.
If you can appreciate old art and animation it's easy to say both shows still look great to this day, with the exception of Ideon's recurring stock footage here and there. The Harlock series has better pacing and a much more likeable and developed cast all around, while Ideon is strikingly a bit more darker in tone and very desperate in nature. Both have incredibly impressive soundtracks, orchestrated and all. By the end of these two shows you yourself might be out of breath, as you'll feel like you went through these huge adventures personally. Typical of Tomino stuff Ideon is a little quirkier at times and has mecha, but overall the show is far more space drama than some of his other works. Overall, both have a lot of similar themes and ideas, with very different styles and executions in terms of writing/directing. But in the end these are two amazing, action packed, and adventure filled classic space dramas.
And please note: Be Invoked IS the ending to Ideon. Episode 39 is just a sampler. read more
Same creator, same concept. Densetsu Kyojin Ideon was the series Yoshiyuki Tomino did after Mobile Suite Gundam ended. It has the same setup: Teenage boy is the only one who can pilot the giant mecha. A group of humans are forced to leave their homes and wander space, always on the run from the same bad guys, go through personal stuff, etc. Teenage boy piloting the mecha must protect the group, with assistance from a handful of companions. It's a slightly different take on the character types and relationships, and the Ideon is made up of three separate component vehicles, originally created by some alien civilization. read more
You can't get more "Kill em' All" Tomino than these two ... both can be a hit or miss though, I personally didn't like Victory too much but loved Ideon. I'm sure many are different on that, or may agree, might love or hate both, etc! All in all though if you want brutally grim Tomino shows, these are it.