Is it good? Hmmm. Don't know if I'd go that far. It looks bloody awful, the stories are simplistic and it's not actually that interesting. However it's horror and mostly fairly okay at telling a bunch of sinister monster tales.
At first it's just an anthology show. People meet monsters and regret it, often briefly. (There's no such thing as a gentle, vegetarian monster in this show.) Ep.1 does the Loch Ness Monster, ep.2 does the Yeti and then after that the show's doing more original horrors.
Well, sort of. I'm simplifying. In fact those famous monsters I named have Japanese equivalents and it'll be those we're seeing here, not the ones you've heard of. Ep.1 presumably features Kusshii or Issie, which are Nessie-like Japanese lake monsters said to live in Lake Kussharo and Lake Ikeda. Ep.2 stars the Hibagon. I've also read that ep.4 might be doing the Beast of Busco (Indiana, 1949) and that ep.5 might loosely be based on the Loveland frog (Ohio, 1955 onwards). However after that we're into the great-granddaddy of the Creature from the Black Lagoon and the Graboids from Tremors, so I don't think we need to get too literal-minded about all this forteana.
These are reasonably good horror shorts. Some of them even manage to be a bit scary here and there. (I'm not damning with faint praise there, since genuine fear isn't easy to do and there's lots of so-called horror that doesn't manage it.) However there's no point in trying to marathon these episodes, because it's an anthology format and nothing follows on from anything else.
...but in fact that's wrong. The show does actually have a plot. There's a scarred monster researcher in a dark suit called Sousuke Banba who keeps showing up. He's nice, but fairly bland. Later we meet his friend/rival, Masaki Kimura, who wears a white suit and appears to be a good deal less nice. Masaki is scarier and hence more satisfying in a horror show, since he's capable of sending in men with flamethrowers without any noticeable concern for any people at the scene who might be still alive. For him, all this is a business opportunity. "Where's the profit in chasing after nearly unkillable mass-murdering monsters?" I hear you ask. Well...
In the end, the plot's quite satisfying. The monster incidents get tied together in hindsight and there's an ultimate monster, the Kagewani of the title. (This means "shadow crocodile" and it's a really weird one.) Sousuke and Masaki graduate from being ongoing guest stars to being the show's protagonists.
If the show looked better, I might have almost recommended it. The episodes are okay-to-decent rather than special and the only really remarkable thing about the show's story arc is the fact that it exists, but there's some decent horror here. However the animation is dog-ugly. It's Flash animation of fixed 2D shapes that often gave me the impression of being heavily Photoshopped photoreference, not artwork. At its worst, it looks like a Monty Python cartoon. It's dire. It would be hard to do this in any other genre, although perhaps you could argue that these non-mimetic visuals add to the monsters' creepiness and make you more accepting of abstract weird stuff like the Kagewani itself.
It's okay. I plodded through it. There were some surprisingly decent individual episodes, but overall I don't think I really cared very much. Upsides: horror ideas and vignettes. Downsides: the art, fairly uninvolving regular character. There's nothing really wrong with it, though. If you like horror anthology shows, you might well like this.