This is certainly a very good looking demo; the graphics are good and movement feels very natural.
I have to echo a couple of points made so far: the pickup prompt appears after your first death (and doesn't appear if you find an item before that); it tries to launch Discord on startup; and there seems to be no way to access the pause menu (I'm using keyboard).
The tutorial text is fine, but they're not necessarily located in the best places; I had fallen to my death several times before I learned I could roll, and I lost a further life to the monster before I discovered I could lock on.
One negative thing I would note about the graphics is that the lack of borders to platforms can make it difficult to see where the edges are, when the edge and the ground are both the same colour.
Unfortunately, the one thing that really didn't click with me was the combat. The strike-timing combo itself is fine, although I never could tell why some times a "hit" would still break the combo instead of continuing it (what I assumed to be an energy gauge next to the health bar never changed). More annoyingly, starting a combo will lock Tikal in place until the combo ends, while the enemy is free to attack; I've seen other people mentioning the ability to dodge, but I couldn't find any key that would let me do this, as both movement and jumping were disabled. This meant that it was usually better to attack twice to immediately break the combo than to play it the way it was actually intended to be played.
I think that one improvement that would mitigate a lot of these issues would be to have the key bindings visible (and maybe even changeable) from the start menu. Also, it would be nice to have opponents who are somewhere in difficulty between the immobile targets and the monster and robot.
Thanks for reading, and good luck with the game!