The Hidden World isn't as good as first two but still good, A-

While it doesn't quit live up to it's predecessors, The Hidden World still has a good story, wonderful animation, and a relatively decent villain that fans of all ages will enjoy.

All of your favorite How to Train Your Dragon characters are back in the Hidden World, the final and third film in the How to Train Your Dragon series. Everyone's favorite Hiccup and Astrid are back, and of course, Toothless and all of his lovable dragons make a soaring return. However, The Hidden Dragon isn't a perfect animated film, and it does fall short from the first two for several reasons. However, those reasons are minor and it's still a great way for the trilogy to end and will bring smiles to both adults and children alike.

As great as Hiccup's band of viking friends are, and their characters are even better and have more screen time in this film, the film would have benefited from actually focusing more on Hiccup and Astrid's relationship. Of course, Hiccup and Toothless are wonderful every time they are on screen together, and we couldn't have asked for anything more in those regards.
The film also lacks a great villain story,  and although Grimmel is wonderfully voiced by Abraham, his character could definitely need some improvements. The final viking battle was just sub par compared to the fights Hiccup had to endure in the first two films.

The Hidden Dragon was a bit short as well, and could have benefited from being longer, especially being the final film in the series and that way, the movie could have added more story line to the villain and Hiccup's and Astrid relationship, while at the same time still having fun with the side characters.

However, besides all of that, The Hidden World mostly soars especially when it focuses on Toothless. Toothless's relationship with the new Light Fury is priceless, and how they finally present the Hidden World is nothing short of amazing animation.
The ending was done extremely well, and the movie might has well have been named 'How to End Your Trilogy'. It ends on a high and loving note, something that the series has done very well with each of its films. It might not be perfect, but the Hidden World is still a good addition to the franchise and represents a great Non Disney ending to a beloved series.

A-