I like the minimalistic graphics and sounds, but it's still buggy and the gameplay mechanics aren't very good.
1) There's no way to escape from an enemy. This - coupled with the fact that player attacks and enemy attacks occur simultaneously - makes the game predominantly about luck. You should really add an option to flee, but have it incur a penalty as well (like the high probability of HP damage, loss of gold, or loss of a random item).
2) The player's maximum HP doesn't increase as s/he levels up, and it should. Also, Healing Potions are waaaaaay too costly for the lousy +2HP they give. Right now it's more cost efficient to just use Monster Killers as much as possible and then fall back to attacking when you run out.
3) Why would anyone leave the first dungeon floor if all the enemies give 2 EXP regardless of how much HP they have or how much damage they do? A slime on the first floor has 5 HP, 1 ATK, and gives 2 EXP; red knight on the third floor has 20 HP, 2 ATK, and gives 2 EXP.
4) The game is still very buggy. The only quest that I got to work was "Collect 5 items". The first time I went down a ladder, the game screen went all black and I had to refresh the page. You can amass an infinite amount of gold at any shop because of a bug that allows weapon duping. Click where your equipped weapon box would be, and then sell the duped weapon in your inventory. Repeat as necessary.