A very solid entry! The spear mechanic its really good, and i'm sure you can expand on it (more blessings, the red one I found wasn't that useful). And I also think you did a really good job with enemy variety and the bosses!
The HUD although looks nice, it's a little bit too big, and sometimes would obscure too much of the screen. Also the screens/areas feel too big and with too much empty space, which makes them hard to navigate, and makes a lot of it feel too samey.
You did put in the description that the terrain was more detailed on purpose but I think it would be better to just stick with one or two art styles (you had pixel art for characters, more high resolution for terrain, and simple drawings for the background), it clashed a bit too much.
(I ended up reaching the end of the demo, so defeated 2 bosses, colloseum, and got the dash)
Lastly, I think the combat was serviceable, but only being able to hit to the sides felt too restrictive with having flying enemies, and probably adding a little bit more feedback to it (some more knockback, maybe a bigger hitbox for the attack) would make it feel a lot better.