Better the less you know about it
Tunic is one of those games that's better the less you know about it. It's worth buying, but there is something to keep in mind before you do. Screenshots and videos might give the impression that it's a typical casual Zelda-like game, and in some ways it is, but it's deceptively cryptic and challenging. It reminded me of last year's Metroid Dread, with some specific situations requiring trial, error and practice to overcome. It is Nintendo Hard, and some people don't want that. I sometimes found myself spending a lot of time running around trying to find the one thing I was missing in order to proceed. Make no mistake, Tunic is far more like Zelda 1 than it is Wind Waker. If getting good and trying everything you can think of to move along appeals to you, then stop reading this review and go play the game now, you won't be disappointed.
If you're still not sure, I want to bring up the in-game instruction manual. Throughout the game, you'll find sheets of an instruction manual similar to the ones you'd get with an NES game - more obvious Zelda influence. They aren't just novel, they serve an important purpose. The vast majority of text in Tunic, from sign posts, dialog and other various text boxes, is a made-up language that very much look like moon runes. Often just a few words and sentences will be in English, and the instruction manual is no exception. Most of it is unreadable, but by finding pages and piecing together the information and clues from it, you're learning more about the game while still preserving the sense of mystery lost on modern games. It's weirdly meta, but pure genius.
Good responsive action, well-hidden secrets and a vivid visual style coalesce with the above into a game that is reminiscent of the pre-internet era, capturing what made the first Zelda so magical for the generation that played it when it was new. If you want to experience that again, or never had that chance, play Tunic. It's one I wish I could play again for the first time.