Mazinkaiser is an OAV re-imagining of the Mazinger Z story that was released in 2001. It tells the story of how Kouji Kabuto discovers and masters his grandfather's final legacy, the most powerful of the Mazingers.Mazinkaiser originally appeared in Super Robot Wars F Final, when Banpresto asked Go Nagai to design a new mecha for Kouji to use as a Mid-Season Upgrade. The idea was for Mazinger Z being upgraded through the exposure of Getter Rays into a new monstrous form, later redubbing it the Mazinkaiser; Alpha 1, the start of the next "major" SRW storyline, revamped the origin of the robot into being the original Mazinger Super Prototype that ended up being too super and difficult to control, necessitating its sealing away until Kouji finds it and tames it. (This version also conveniently fills out a long-standing plot gap of "what was the accident that nearly killed Kenzo and his wife?" in the Mazinger mythology.) The idea was such a hit with fans that Go Nagai quickly incorporated it into Mazinger canon in anime and manga form, using the Alpha version of the origin story.During a massive attack by Mad Scientist Dr. Hell's mechanical beasts, the Mazinger Z and Great Mazinger both sortie to battle, but are eventually overrun through sheer numbers. Kouji's Hover Pilder is ripped from Mazinger Z and hurled from the battlefield, and Mazinger Z itself is captured by Dr. Hell, who turns it into a mechanical devil for his own purposes and sends it against the Photonic Research Institute. Outnumbered, Tetsuya Tsurugi goes to battle with a damaged Great Mazinger when suddenly a new, insanely powerful and more demonic looking Mazinger shows up with Kouji at the helm...The OAV ran for seven episodes, and was followed up by the movie Mazinkaiser VS the Great General of Darkness, where the Mycene Empire invades while Kouji is vacationing in Paris, forcing him to fight his way back to Japan and take Mazinkaiser into battle once more.There's also a second OAV series, Mazinkaiser SKL. This particular take is a very different re-imagining, with all-new characters. It looks a Mazinkaiser-meets-Super Robot Wars Gaiden-meets-Super Robot Wars Compact 3 mix. We're not sure how that will work out, but It looks pretty damn cool.This series contains examples of:
Breath Weapon: Rust Tornado, an Up to Eleven version of Mazinger's Rust Hurricane, combined with Great Mazinger's Great Typhoon: Mazinkaiser blows several jets of particle-charged wind from its mouth grill that corrodes the enemy into nothingness (assuming the terrifying gale winds did not break it apart first). Its huge destructive force dug a ditch through a side of Mount Fuji.
Brought Down to Badass : For some reason, Tetsuya switched back into old Great Mazinger in the movie. He still made the most awesome moments AND as kickass as ever.
Convection Schmonvection: In one episode, Mazinkaiser got dunked in lava. Since Mazinkaiser was Made of Indestructium, Kouji could survive for a short while in that enviroment, but all knew they had to get him out of the volcano QUICKLY, or he would die.
Distracted by the Sexy: It happened fairly often in the original manga. Usually was Sayaka the one did the -unwilling- distraction -either because her clothes were torn or because she was involuntarily naked-, but sometimes it was done by enemies to distract Kouji. One of those scenes was animated in the Beach Episode: Kouji accidentally undoes Sayaka's topnote he was trying to grab her shoulder and missed; she's actually more upset by Boss getting a look at her breasts than she is by Kouji, even though he weaponizes her boobs in order to escape the enemy fortress.
Exactly What I Aimed At: In the movie, Tetsuya is fighting Angoras and Scarabeth, two commanders of the Mykene Empire army. Tetsuya throws Great Mazinger's Great Boomerang and right after shoots Great Typhoon. Both attacks miss, both commanders laugh and ask where he is aiming at... when Great Mazinger's boomerang slices them both from behind. As he is dying, Scarabeth -Mykene army's best tactician- realizes Tetsuya had missed his boomerang throw on purpose, and he shot Great Typhoon to change the boomerang's trajectory. So he caught them by surprise and killed both of them at once.
Fan Disservice (A naked Baron Ashura?! MY EYES!! MY BEAUTIFUL EYES!!!!)
Fortunately for us, it doesn't show the squicky bits at all. In fact, it's hilarious in context)
The Guards Must Be Crazy (Apparently Baron Ashura's mooks can't tell the difference between Boss in a helmet and one of their co-workers. The mooks that were assigned to guard him and Kouji specifically, no less)
Gainaxing: Lori and Roll do this plenty of times, as do the three androids.
JAM Project ("Fire Wars", "The Gate of Hell", and "Mazin Kenzan")
Large Ham (If the dub acting was any hammier, you could serve it for Christmas dinner. Special attention goes to Dr. Hell, who is chewing so much scenery that his fortress should be collapsing around him.)
Lava is Boiling Kool-Aid: In one episode Mazinkaiser (with Kouji inside it) was tossed into the crater of Mount Fuji (paying homage to an episode of the original series). Kouji fainted due to the extreme heat and sheer pressure... and that was it. The characters pointed out not even Mazinkaiser could endure that for long and they had to get Kouji out of the magma RIGHT AWAY, though. The lava also seems less dangerous than it should be (it is too bright, too fluid and not viscous enough). However, given what kind of punishment Mazinkaiser shrugs off throughout the series, withstanding a lava bath seems almost trivial.
Let's Get Dangerous (Two twins Lorry and Roll are fanservicy, yeah. But when it's time to get serious, they show that they're more than just Fanservice: see episode 5, i.e.)
They also show their stuff in the movie, what with piloting a Fembot and all. Too bad that's where they die.
Made of Indestructium: Mazinkaiser takes this concept and RUNS WITH IT. Nothing seems being capable to even scratch it. This video should show it convincingly: 
Super Mode (The SRW version has two: "Devil" mode, which makes the Mazinkaiser go sentient and berserk, and "God" mode, which is theorized to be on par with a full-powered SRW Shin Getter Robo). SRW games also has Mazinpower that activates at 130 will giving a power boost
While Super Robot Wars series in general has a problem with damage numbers, its pretty notable that Mazinkaiser is possibly the biggest and long running offender of Statistically Speaking. Thanks to its Super Mode that increase attack, Not only it deals damage higher than Glass Cannon like Getter Robo, it also tanks better. Not to mention the issue of having some of its weaker attack dealing higher damage than other mech's final attack most notably the sun-killing Goldion Crusher from GaoGaiGar being slightly weaker than Final Kaiser Blade.
Tsundere (Variation. Sayaka was a Type A (tsuntsun) in the original series, but she mellows out a bit and is mostly a Type B (deredere), like in the manga.
Telescoping Robot: Mazinkaiser had THREE blades hid into its body (two of them into its shoulders and the bigger into its chest), and its midsection stored one giant missile.
Truer To The Text: Despite the introduction of Mazinkaiser, in some ways this is closer to the original Mazinger Z manga than the TV series - like a much closer art style to Nagai's, and Gamia Q appearing.
Breath Weapon: The Rust Tornado, which still has the corrosive component
Chest Blaster: The Fire Blaster; notably, it's theorzied the Fire Blaster can punch a hole through to the Earth's core; it's so powerful that even though the main blast goes over a bunch of mechanical beasts, the sheer heat of it still melts them anyhow).
Also technically the Gigant Missile, though it comes from Kaiser's navel.