That's a huge project! It looks like a collaboration between Diablo, Don't Starve and many other devs. A lot of other submissions revolve around one or few simple mechanics and ideas. This game is different because there are just too many sides. The gameplay changes between exploring (swimming), fighting, revealing the story (lore), and completing the quest. Graphics is both 2D and 3D. The game seems to include a bit of everything. If completed and polished to a single style, that would be an impressive game.