Do you like copious amounts of random gore and sex? Literal essays of text to read explaining pointless lore and worldbuilding? Did I mention all the mindless gore and sex?
If this doesn't appeal to you, or if you don't like being bored beyond belief while watching media, Maryuu Senki is not for you.
The 1980s and 1990s are filled with OVAs no human being should ever watch -- content so mindless and boring it's hard to imagine there was ever a target audience for it. This is another one of those, and it's not particularly remarkable among them. The characters are all flat and boring -- new ones appear and disappear on screen, and most of them really don't seem to matter. The plot is chaotic and confusing and basically feels like a vessel to get random fights to occur. It's not bad enough to truly hate, and there's some minor entertainment to be gained from all the action, but it's hard to really say much nice about beyond 'it could be worse'. Honestly, it's hard to even write much about this OVA; I spent nearly two hours watching it and all of it vanished from my brain immediately after. A bunch of random freaky shit happened slowly over a long, boring period and made no sense. There's no baseline competency or rules in play to make the ridiculous things stand out. The third episode spends 15 minutes recapping the previous hour of content and it still feels just as much like nonsensical violence as it did the first time (complete with a side of rape-y overtones). People explode into red puddles, turn into tentacle blobs, and grow third eyes. Our main character (?) is some potter who has a demon inside of him, seemingly dies, and turns into Solomon Grundy before then turning into Arnold Schwarzenegger. Ninjas appear to fight our heroes at random moments, girls become naked for no reason, and at some point our heroes get saved by the appearance of a more attractive version of the Paradox brothers from Yu-Gi-Oh!. All the while, rejected Street Fighter music plays, random definitions of terms flash onscreen, and if I'm making this sound like it's actually fun, characters talk. A lot. About absolutely nothing. Things like how the 'Ingyou Jakan' is about to happen, or the 'Four Holy Beasts', or how they didn't notice that they actually died 18 years ago. Alternatively, about their goddamn occupation as a potter. It would be fascinating if it wasn't completely and utterly boring and inane, since there's no solid ground to even start from. Instead, it just feels like people mindlessly saying and doing things for almost two hours.
If you're looking for a good time, or even just something funny to watch with friends, don't bother with this. (...Unless you really want to see the secret inspiration for Muzan from Demon Slayer. But seriously, don't bother.)
