These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Let's not forget the awesome Majin Kenzan!! insert song in the movie, accompanying Mazinkaiser's triumphant return to Earth, and the ensuing curbstomping it inflicts thereafter. (See the above Dynamic Entry; it's that very scene.)
Also, "Theme of Mazinkaiser" by JAM Project founder (and singer of the original Mazinger Z theme) Ichiro Mizuki.
God-Mode Sue (Arguably, the Mazinkaiser, because nothing can destroy it, not even drowning it in molten lava. Probably one of the few robots to never gets its paintjob scratched too.)
Not 100% sure, since its Super Mode takes a while to control and Kouji does have lotsa trouble with it at first, almost destroying both the Institute and Great Mazinger and seriously injuring Tetsuya during its rampage.)
Still goddamn awesome. Besides, Mazinkaiser may never get its paintjob scratched, but Kouji can still take damage when riding it.
Let's not forget Mazinkaiser's Dynamic Entry in the movie, where Kouji docks with it while it's plummeting to the ground from orbit, creates a huge crater when it crashes, killing several mechanical beasts in the proccess, then comes out completely unharmed while proceeding to destroy several more high-level mechanical beasts, all in less than 5 minutes! It just gets better from there.