Thank you for making the demo version available! I like the demo version so far, but I prefer to use the Arrow keys instead of AWSD (it should be made an option that you can choose what keys you want for movement, jump, attack, etc.)). I did not see any options for music/sounds volume and the music was a little quiet for me (good music gets me more engaged with a game). And you made this 2D game in CopperCube? Very impressive! I like the graphics and the water effects!
It's a little difficult to tell when I've hit an enemy/creature (I just slash like crazy til it falls). Maybe add a colored strike effect (flash?) or something?
If you're interested in expanding the music offerings (how many does this game have?), I've composed music for two people on Ambiera forums as well as for my own iOS game, Lava Crew, and my CopperCube game, "Luposian: Prelude to Creation".
I'll play this game again tomorrow and when I've finished it, I'll likely buy the full version. I think it's worth it! But please take my suggestions into consideration. I think it would improve game play and engagement for players.