Large flaws...
First off, the grammar is terrible. If you ever need a text editor, send me a PM and we can communicate through NG or through emails. Secondly, there's NO save feature, not even autosave!? I had to restart my browser due to severe Flash lag, only to come back and see that all the money I had made by repeatedly grinding the Training mission was lost, and I was forced to start back at the first mission.
If you're going to make an RPG-type side-scroller with unlockable skills, levels, items, etc., you darn well better include the ability to save, otherwise people are going to play once and never come back. As a gamer, it's annoying to spend time grinding money and exp to increase a character's level and buy new items when you're just going to lose it all anyway.
Another reason for my low score is that this game looks like a Maplestory clone... I haven't actually played Maplestory, but I've seen what the sprites look like, and this looks like it's some Flash knockoff. Not that it's normally a bad thing to imitate another game or a game's animation style, but usually when the similarity between games is so significant, the creator might want to at least state "inspired by Maplestory" or something to that effect.
Bosses tend to be immune to all attacks when they are attacking, which doesn't really seem realistic or fair... in most games, if an ability takes a certain amount of time to charge up, taking damage usually either cancels the ability or delays it. Additionally, the hitboxes weren't perfect... sometimes, enemies could hit my character when I couldn't hit them back.
Add in a save feature, correct the spelling and grammar, and revise the hitboxes, and you'll have a game that people will spend some time on... until then, I think it's going to be a one-play type of game.